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# This Python file uses the following encoding: utf-8
# It has been edited by fix-complaints.py .

#############################################################################
##
## Copyright (C) 2019 The Qt Company Ltd.
## Contact: https://www.qt.io/licensing/
##
## This file is part of Qt for Python.
##
## $QT_BEGIN_LICENSE:LGPL$
## Commercial License Usage
## Licensees holding valid commercial Qt licenses may use this file in
## accordance with the commercial license agreement provided with the
## Software or, alternatively, in accordance with the terms contained in
## a written agreement between you and The Qt Company. For licensing terms
## and conditions see https://www.qt.io/terms-conditions. For further
## information use the contact form at https://www.qt.io/contact-us.
##
## GNU Lesser General Public License Usage
## Alternatively, this file may be used under the terms of the GNU Lesser
## General Public License version 3 as published by the Free Software
## Foundation and appearing in the file LICENSE.LGPL3 included in the
## packaging of this file. Please review the following information to
## ensure the GNU Lesser General Public License version 3 requirements
## will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
##
## GNU General Public License Usage
## Alternatively, this file may be used under the terms of the GNU
## General Public License version 2.0 or (at your option) the GNU General
## Public license version 3 or any later version approved by the KDE Free
## Qt Foundation. The licenses are as published by the Free Software
## Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
## included in the packaging of this file. Please review the following
## information to ensure the GNU General Public License requirements will
## be met: https://www.gnu.org/licenses/gpl-2.0.html and
## https://www.gnu.org/licenses/gpl-3.0.html.
##
## $QT_END_LICENSE$
##
#############################################################################

from __future__ import print_function

"""
PSF LICENSE AGREEMENT FOR PYTHON 3.7.0

1. This LICENSE AGREEMENT is between the Python Software Foundation ("PSF"), and
   the Individual or Organization ("Licensee") accessing and otherwise using Python
   3.7.0 software in source or binary form and its associated documentation.

2. Subject to the terms and conditions of this License Agreement, PSF hereby
   grants Licensee a nonexclusive, royalty-free, world-wide license to reproduce,
   analyze, test, perform and/or display publicly, prepare derivative works,
   distribute, and otherwise use Python 3.7.0 alone or in any derivative
   version, provided, however, that PSF's License Agreement and PSF's notice of
   copyright, i.e., "Copyright © 2001-2018 Python Software Foundation; All Rights
   Reserved" are retained in Python 3.7.0 alone or in any derivative version
   prepared by Licensee.

3. In the event Licensee prepares a derivative work that is based on or
   incorporates Python 3.7.0 or any part thereof, and wants to make the
   derivative work available to others as provided herein, then Licensee hereby
   agrees to include in any such work a brief summary of the changes made to Python
   3.7.0.

4. PSF is making Python 3.7.0 available to Licensee on an "AS IS" basis.
   PSF MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED.  BY WAY OF
   EXAMPLE, BUT NOT LIMITATION, PSF MAKES NO AND DISCLAIMS ANY REPRESENTATION OR
   WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR THAT THE
   USE OF PYTHON 3.7.0 WILL NOT INFRINGE ANY THIRD PARTY RIGHTS.

5. PSF SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON 3.7.0
   FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS A RESULT OF
   MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON 3.7.0, OR ANY DERIVATIVE
   THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.

6. This License Agreement will automatically terminate upon a material breach of
   its terms and conditions.

7. Nothing in this License Agreement shall be deemed to create any relationship
   of agency, partnership, or joint venture between PSF and Licensee.  This License
   Agreement does not grant permission to use PSF trademarks or trade name in a
   trademark sense to endorse or promote products or services of Licensee, or any
   third party.

8. By copying, installing or otherwise using Python 3.7.0, Licensee agrees
   to be bound by the terms and conditions of this License Agreement.
"""

__doc__ = """
    signature() - get a Signature object for the callable
"""

import sys
from collections import OrderedDict

CO_OPTIMIZED    = 0x0001
CO_NEWLOCALS    = 0x0002
CO_VARARGS      = 0x0004
CO_VARKEYWORDS  = 0x0008
CO_NESTED       = 0x0010
CO_GENERATOR    = 0x0020
CO_NOFREE       = 0x0040


###############################################################################
### Function Signature Object (PEP 362)
###############################################################################


# This function was changed: 'builtins' and 'qualname' don't exist.
# We use '__builtin__' and '__name__' instead.
def formatannotation(annotation, base_module=None):
    if getattr(annotation, '__module__', None) == 'typing':
        return repr(annotation).replace('typing.', '')
    if isinstance(annotation, type):
        if annotation.__module__ in ('__builtin__', base_module):
            return annotation.__name__
        return annotation.__module__+'.'+annotation.__name__
    return repr(annotation)


def _signature_is_functionlike(obj):
    """Private helper to test if `obj` is a duck type of FunctionType.
    A good example of such objects are functions compiled with
    Cython, which have all attributes that a pure Python function
    would have, but have their code statically compiled.
    """

    if not callable(obj) or isclass(obj):
        # All function-like objects are obviously callables,
        # and not classes.
        return False

    name = getattr(obj, '__name__', None)
    code = getattr(obj, '__code__', None)
    defaults = getattr(obj, '__defaults__', _void) # Important to use _void ...
    kwdefaults = getattr(obj, '__kwdefaults__', _void) # ... and not None here
    annotations = getattr(obj, '__annotations__', None)

    return (isinstance(code, types.CodeType) and
            isinstance(name, str) and
            (defaults is None or isinstance(defaults, tuple)) and
            (kwdefaults is None or isinstance(kwdefaults, dict)) and
            isinstance(annotations, dict))



def _signature_from_function(cls, func):
    """Private helper: constructs Signature for the given python function."""

    is_duck_function = False
    if not isfunction(func):
        if _signature_is_functionlike(func):
            is_duck_function = True
        else:
            # If it's not a pure Python function, and not a duck type
            # of pure function:
            raise TypeError('{!r} is not a Python function'.format(func))

    Parameter = cls._parameter_cls

    # Parameter information.
    func_code = func.__code__
    pos_count = func_code.co_argcount
    arg_names = func_code.co_varnames
    positional = tuple(arg_names[:pos_count])
    keyword_only_count = 0 # func_code.co_kwonlyargcount
    keyword_only = arg_names[pos_count:(pos_count + keyword_only_count)]
    annotations = func.__annotations__
    defaults = func.__defaults__
    kwdefaults = func.__kwdefaults__

    if defaults:
        pos_default_count = len(defaults)
    else:
        pos_default_count = 0

    parameters = []

    # Non-keyword-only parameters w/o defaults.
    non_default_count = pos_count - pos_default_count
    for name in positional[:non_default_count]:
        annotation = annotations.get(name, _empty)
        parameters.append(Parameter(name, annotation=annotation,
                                    kind=_POSITIONAL_OR_KEYWORD))

    # ... w/ defaults.
    for offset, name in enumerate(positional[non_default_count:]):
        annotation = annotations.get(name, _empty)
        parameters.append(Parameter(name, annotation=annotation,
                                    kind=_POSITIONAL_OR_KEYWORD,
                                    default=defaults[offset]))

    # *args
    if func_code.co_flags & CO_VARARGS:
        name = arg_names[pos_count + keyword_only_count]
        annotation = annotations.get(name, _empty)
        parameters.append(Parameter(name, annotation=annotation,
                                    kind=_VAR_POSITIONAL))

    # Keyword-only parameters.
    for name in keyword_only:
        default = _empty
        if kwdefaults is not None:
            default = kwdefaults.get(name, _empty)

        annotation = annotations.get(name, _empty)
        parameters.append(Parameter(name, annotation=annotation,
                                    kind=_KEYWORD_ONLY,
                                    default=default))
    # **kwargs
    if func_code.co_flags & CO_VARKEYWORDS:
        index = pos_count + keyword_only_count
        if func_code.co_flags & CO_VARARGS:
            index += 1

        name = arg_names[index]
        annotation = annotations.get(name, _empty)
        parameters.append(Parameter(name, annotation=annotation,
                                    kind=_VAR_KEYWORD))

    # Is 'func' is a pure Python function - don't validate the
    # parameters list (for correct order and defaults), it should be OK.
    return cls(parameters,
               return_annotation=annotations.get('return', _empty),
               __validate_parameters__=is_duck_function)




class _void(object):
    """A private marker - used in Parameter & Signature."""


class _empty(object):
    """Marker object for Signature.empty and Parameter.empty."""


class _ParameterKind(object): # (enum.IntEnum):
    POSITIONAL_ONLY = 0
    POSITIONAL_OR_KEYWORD = 1
    VAR_POSITIONAL = 2
    KEYWORD_ONLY = 3
    VAR_KEYWORD = 4

    def __str__(self):
        return self._name_


_POSITIONAL_ONLY         = _ParameterKind.POSITIONAL_ONLY
_POSITIONAL_OR_KEYWORD   = _ParameterKind.POSITIONAL_OR_KEYWORD
_VAR_POSITIONAL          = _ParameterKind.VAR_POSITIONAL
_KEYWORD_ONLY            = _ParameterKind.KEYWORD_ONLY
_VAR_KEYWORD             = _ParameterKind.VAR_KEYWORD


class Parameter(object):
    """Represents a parameter in a function signature.

    Has the following public attributes:

    * name : str
        The name of the parameter as a string.
    * default : object
        The default value for the parameter if specified.  If the
        parameter has no default value, this attribute is set to
        `Parameter.empty`.
    * annotation
        The annotation for the parameter if specified.  If the
        parameter has no annotation, this attribute is set to
        `Parameter.empty`.
    * kind : str
        Describes how argument values are bound to the parameter.
        Possible values: `Parameter.POSITIONAL_ONLY`,
        `Parameter.POSITIONAL_OR_KEYWORD`, `Parameter.VAR_POSITIONAL`,
        `Parameter.KEYWORD_ONLY`, `Parameter.VAR_KEYWORD`.
    """

    __slots__ = ('_name', '_kind', '_default', '_annotation')

    POSITIONAL_ONLY         = _POSITIONAL_ONLY
    POSITIONAL_OR_KEYWORD   = _POSITIONAL_OR_KEYWORD
    VAR_POSITIONAL          = _VAR_POSITIONAL
    KEYWORD_ONLY            = _KEYWORD_ONLY
    VAR_KEYWORD             = _VAR_KEYWORD

    empty = _empty

    def __init__(self, name, kind, default=_empty, annotation=_empty):

        if kind not in (_POSITIONAL_ONLY, _POSITIONAL_OR_KEYWORD,
                        _VAR_POSITIONAL, _KEYWORD_ONLY, _VAR_KEYWORD):
            raise ValueError("invalid value for 'Parameter.kind' attribute")
        self._kind = kind

        if default is not _empty:
            if kind in (_VAR_POSITIONAL, _VAR_KEYWORD):
                msg = '{} parameters cannot have default values'.format(kind)
                raise ValueError(msg)
        self._default = default
        self._annotation = annotation

        if name is _empty:
            raise ValueError('name is a required attribute for Parameter')

        if not isinstance(name, str):
            raise TypeError("name must be a str, not a {!r}".format(name))

        if name[0] == '.' and name[1:].isdigit():
            # These are implicit arguments generated by comprehensions. In
            # order to provide a friendlier interface to users, we recast
            # their name as "implicitN" and treat them as positional-only.
            # See issue 19611.
            if kind != _POSITIONAL_OR_KEYWORD:
                raise ValueError(
                    'implicit arguments must be passed in as {}'.format(
                        _POSITIONAL_OR_KEYWORD
                    )
                )
            self._kind = _POSITIONAL_ONLY
            name = 'implicit{}'.format(name[1:])

        if not True: # name.isidentifier():
            raise ValueError('{!r} is not a valid parameter name'.format(name))

        self._name = name

    def __reduce__(self):
        return (type(self),
                (self._name, self._kind),
                {'_default': self._default,
                 '_annotation': self._annotation})

    def __setstate__(self, state):
        self._default = state['_default']
        self._annotation = state['_annotation']

    @property
    def name(self):
        return self._name

    @property
    def default(self):
        return self._default

    @property
    def annotation(self):
        return self._annotation

    @property
    def kind(self):
        return self._kind

    def replace(self, name=_void, kind=_void,
                annotation=_void, default=_void):
        """Creates a customized copy of the Parameter."""

        if name is _void:
            name = self._name

        if kind is _void:
            kind = self._kind

        if annotation is _void:
            annotation = self._annotation

        if default is _void:
            default = self._default

        return type(self)(name, kind, default=default, annotation=annotation)

    def __str__(self):
        kind = self.kind
        formatted = self._name

        # Add annotation and default value
        if self._annotation is not _empty:
            formatted = '{}: {}'.format(formatted,
                                       formatannotation(self._annotation))

        if self._default is not _empty:
            formatted = '{}={}'.format(formatted, repr(self._default))

        if kind == _VAR_POSITIONAL:
            formatted = '*' + formatted
        elif kind == _VAR_KEYWORD:
            formatted = '**' + formatted

        return formatted

    def __repr__(self):
        return '<{} "{}">'.format(self.__class__.__name__, self)

    def __hash__(self):
        return hash((self.name, self.kind, self.annotation, self.default))

    def __eq__(self, other):
        if self is other:
            return True
        if not isinstance(other, Parameter):
            return NotImplemented
        return (self._name == other._name and
                self._kind == other._kind and
                self._default == other._default and
                self._annotation == other._annotation)


class BoundArguments(object):
    """Result of `Signature.bind` call.  Holds the mapping of arguments
    to the function's parameters.

    Has the following public attributes:

    * arguments : OrderedDict
        An ordered mutable mapping of parameters' names to arguments' values.
        Does not contain arguments' default values.
    * signature : Signature
        The Signature object that created this instance.
    * args : tuple
        Tuple of positional arguments values.
    * kwargs : dict
        Dict of keyword arguments values.
    """

    __slots__ = ('arguments', '_signature', '__weakref__')

    def __init__(self, signature, arguments):
        self.arguments = arguments
        self._signature = signature

    @property
    def signature(self):
        return self._signature

    @property
    def args(self):
        args = []
        for param_name, param in self._signature.parameters.items():
            if param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY):
                break

            try:
                arg = self.arguments[param_name]
            except KeyError:
                # We're done here. Other arguments
                # will be mapped in 'BoundArguments.kwargs'
                break
            else:
                if param.kind == _VAR_POSITIONAL:
                    # *args
                    args.extend(arg)
                else:
                    # plain argument
                    args.append(arg)

        return tuple(args)

    @property
    def kwargs(self):
        kwargs = {}
        kwargs_started = False
        for param_name, param in self._signature.parameters.items():
            if not kwargs_started:
                if param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY):
                    kwargs_started = True
                else:
                    if param_name not in self.arguments:
                        kwargs_started = True
                        continue

            if not kwargs_started:
                continue

            try:
                arg = self.arguments[param_name]
            except KeyError:
                pass
            else:
                if param.kind == _VAR_KEYWORD:
                    # **kwargs
                    kwargs.update(arg)
                else:
                    # plain keyword argument
                    kwargs[param_name] = arg

        return kwargs

    def apply_defaults(self):
        """Set default values for missing arguments.

        For variable-positional arguments (*args) the default is an
        empty tuple.

        For variable-keyword arguments (**kwargs) the default is an
        empty dict.
        """
        arguments = self.arguments
        new_arguments = []
        for name, param in self._signature.parameters.items():
            try:
                new_arguments.append((name, arguments[name]))
            except KeyError:
                if param.default is not _empty:
                    val = param.default
                elif param.kind is _VAR_POSITIONAL:
                    val = ()
                elif param.kind is _VAR_KEYWORD:
                    val = {}
                else:
                    # This BoundArguments was likely produced by
                    # Signature.bind_partial().
                    continue
                new_arguments.append((name, val))
        self.arguments = OrderedDict(new_arguments)

    def __eq__(self, other):
        if self is other:
            return True
        if not isinstance(other, BoundArguments):
            return NotImplemented
        return (self.signature == other.signature and
                self.arguments == other.arguments)

    def __setstate__(self, state):
        self._signature = state['_signature']
        self.arguments = state['arguments']

    def __getstate__(self):
        return {'_signature': self._signature, 'arguments': self.arguments}

    def __repr__(self):
        args = []
        for arg, value in self.arguments.items():
            args.append('{}={!r}'.format(arg, value))
        return '<{} ({})>'.format(self.__class__.__name__, ', '.join(args))


class Signature(object):
    """A Signature object represents the overall signature of a function.
    It stores a Parameter object for each parameter accepted by the
    function, as well as information specific to the function itself.

    A Signature object has the following public attributes and methods:

    * parameters : OrderedDict
        An ordered mapping of parameters' names to the corresponding
        Parameter objects (keyword-only arguments are in the same order
        as listed in `code.co_varnames`).
    * return_annotation : object
        The annotation for the return type of the function if specified.
        If the function has no annotation for its return type, this
        attribute is set to `Signature.empty`.
    * bind(*args, **kwargs) -> BoundArguments
        Creates a mapping from positional and keyword arguments to
        parameters.
    * bind_partial(*args, **kwargs) -> BoundArguments
        Creates a partial mapping from positional and keyword arguments
        to parameters (simulating 'functools.partial' behavior.)
    """

    __slots__ = ('_return_annotation', '_parameters')

    _parameter_cls = Parameter
    _bound_arguments_cls = BoundArguments

    empty = _empty

    def __init__(self, parameters=None, return_annotation=_empty,
                 __validate_parameters__=True):
        """Constructs Signature from the given list of Parameter
        objects and 'return_annotation'.  All arguments are optional.
        """

        if parameters is None:
            params = OrderedDict()
        else:
            if __validate_parameters__:
                params = OrderedDict()
                top_kind = _POSITIONAL_ONLY
                kind_defaults = False

                for idx, param in enumerate(parameters):
                    kind = param.kind
                    name = param.name

                    if kind < top_kind:
                        msg = 'wrong parameter order: {!r} before {!r}'
                        msg = msg.format(top_kind, kind)
                        raise ValueError(msg)
                    elif kind > top_kind:
                        kind_defaults = False
                        top_kind = kind

                    if kind in (_POSITIONAL_ONLY, _POSITIONAL_OR_KEYWORD):
                        if param.default is _empty:
                            if kind_defaults:
                                # No default for this parameter, but the
                                # previous parameter of the same kind had
                                # a default
                                msg = 'non-default argument follows default ' \
                                      'argument'
                                raise ValueError(msg)
                        else:
                            # There is a default for this parameter.
                            kind_defaults = True

                    if name in params:
                        msg = 'duplicate parameter name: {!r}'.format(name)
                        raise ValueError(msg)

                    params[name] = param
            else:
                params = OrderedDict(((param.name, param)
                                                for param in parameters))

        self._parameters = params # types.MappingProxyType(params)
        self._return_annotation = return_annotation

    @classmethod
    def from_function(cls, func):
        """Constructs Signature for the given python function."""

        warnings.warn("inspect.Signature.from_function() is deprecated, "
                      "use Signature.from_callable()",
                      DeprecationWarning, stacklevel=2)
        return _signature_from_function(cls, func)

    @classmethod
    def from_builtin(cls, func):
        """Constructs Signature for the given builtin function."""

        warnings.warn("inspect.Signature.from_builtin() is deprecated, "
                      "use Signature.from_callable()",
                      DeprecationWarning, stacklevel=2)
        return _signature_from_builtin(cls, func)

    @classmethod
    def from_callable(cls, obj, follow_wrapped=True):
        """Constructs Signature for the given callable object."""
        return _signature_from_callable(obj, sigcls=cls,
                                        follow_wrapper_chains=follow_wrapped)

    @property
    def parameters(self):
        return self._parameters

    @property
    def return_annotation(self):
        return self._return_annotation

    def replace(self, parameters=_void, return_annotation=_void):
        """Creates a customized copy of the Signature.
        Pass 'parameters' and/or 'return_annotation' arguments
        to override them in the new copy.
        """

        if parameters is _void:
            parameters = self.parameters.values()

        if return_annotation is _void:
            return_annotation = self._return_annotation

        return type(self)(parameters,
                          return_annotation=return_annotation)

    def _hash_basis(self):
        params = tuple(param for param in self.parameters.values()
                             if param.kind != _KEYWORD_ONLY)

        kwo_params = {param.name: param for param in self.parameters.values()
                                        if param.kind == _KEYWORD_ONLY}

        return params, kwo_params, self.return_annotation

    def __hash__(self):
        params, kwo_params, return_annotation = self._hash_basis()
        kwo_params = frozenset(kwo_params.values())
        return hash((params, kwo_params, return_annotation))

    def __eq__(self, other):
        if self is other:
            return True
        if not isinstance(other, Signature):
            return NotImplemented
        return self._hash_basis() == other._hash_basis()

    def _bind(self, args, kwargs, partial=False):
        """Private method. Don't use directly."""

        arguments = OrderedDict()

        parameters = iter(self.parameters.values())
        parameters_ex = ()
        arg_vals = iter(args)

        while True:
            # Let's iterate through the positional arguments and corresponding
            # parameters
            try:
                arg_val = next(arg_vals)
            except StopIteration:
                # No more positional arguments
                try:
                    param = next(parameters)
                except StopIteration:
                    # No more parameters. That's it. Just need to check that
                    # we have no `kwargs` after this while loop
                    break
                else:
                    if param.kind == _VAR_POSITIONAL:
                        # That's OK, just empty *args.  Let's start parsing
                        # kwargs
                        break
                    elif param.name in kwargs:
                        if param.kind == _POSITIONAL_ONLY:
                            msg = '{arg!r} parameter is positional only, ' \
                                  'but was passed as a keyword'
                            msg = msg.format(arg=param.name)
                            raise TypeError(msg)# from None
                        parameters_ex = (param,)
                        break
                    elif (param.kind == _VAR_KEYWORD or
                                                param.default is not _empty):
                        # That's fine too - we have a default value for this
                        # parameter.  So, lets start parsing `kwargs`, starting
                        # with the current parameter
                        parameters_ex = (param,)
                        break
                    else:
                        # No default, not VAR_KEYWORD, not VAR_POSITIONAL,
                        # not in `kwargs`
                        if partial:
                            parameters_ex = (param,)
                            break
                        else:
                            msg = 'missing a required argument: {arg!r}'
                            msg = msg.format(arg=param.name)
                            raise TypeError(msg)# from None
            else:
                # We have a positional argument to process
                try:
                    param = next(parameters)
                except StopIteration:
                    raise TypeError('too many positional arguments')# from None
                else:
                    if param.kind in (_VAR_KEYWORD, _KEYWORD_ONLY):
                        # Looks like we have no parameter for this positional
                        # argument
                        raise TypeError(
                            'too many positional arguments')# from None

                    if param.kind == _VAR_POSITIONAL:
                        # We have an '*args'-like argument, let's fill it with
                        # all positional arguments we have left and move on to
                        # the next phase
                        values = [arg_val]
                        values.extend(arg_vals)
                        arguments[param.name] = tuple(values)
                        break

                    if param.name in kwargs:
                        raise TypeError(
                            'multiple values for argument {arg!r}'.format(
                                arg=param.name))# from None

                    arguments[param.name] = arg_val

        # Now, we iterate through the remaining parameters to process
        # keyword arguments
        kwargs_param = None
        for param in itertools.chain(parameters_ex, parameters):
            if param.kind == _VAR_KEYWORD:
                # Memorize that we have a '**kwargs'-like parameter
                kwargs_param = param
                continue

            if param.kind == _VAR_POSITIONAL:
                # Named arguments don't refer to '*args'-like parameters.
                # We only arrive here if the positional arguments ended
                # before reaching the last parameter before *args.
                continue

            param_name = param.name
            try:
                arg_val = kwargs.pop(param_name)
            except KeyError:
                # We have no value for this parameter.  It's fine though,
                # if it has a default value, or it is an '*args'-like
                # parameter, left alone by the processing of positional
                # arguments.
                if (not partial and param.kind != _VAR_POSITIONAL and
                                                    param.default is _empty):
                    raise TypeError('missing a required argument: {arg!r}'. \
                                    format(arg=param_name))# from None

            else:
                if param.kind == _POSITIONAL_ONLY:
                    # This should never happen in case of a properly built
                    # Signature object (but let's have this check here
                    # to ensure correct behavior just in case)
                    raise TypeError('{arg!r} parameter is positional only, '
                                    'but was passed as a keyword'. \
                                    format(arg=param.name))

                arguments[param_name] = arg_val

        if kwargs:
            if kwargs_param is not None:
                # Process our '**kwargs'-like parameter
                arguments[kwargs_param.name] = kwargs
            else:
                raise TypeError(
                    'got an unexpected keyword argument {arg!r}'.format(
                        arg=next(iter(kwargs))))

        return self._bound_arguments_cls(self, arguments)

    def bind(*args, **kwargs):
        """Get a BoundArguments object, that maps the passed `args`
        and `kwargs` to the function's signature.  Raises `TypeError`
        if the passed arguments can not be bound.
        """
        return args[0]._bind(args[1:], kwargs)

    def bind_partial(*args, **kwargs):
        """Get a BoundArguments object, that partially maps the
        passed `args` and `kwargs` to the function's signature.
        Raises `TypeError` if the passed arguments can not be bound.
        """
        return args[0]._bind(args[1:], kwargs, partial=True)

    def __reduce__(self):
        return (type(self),
                (tuple(self._parameters.values()),),
                {'_return_annotation': self._return_annotation})

    def __setstate__(self, state):
        self._return_annotation = state['_return_annotation']

    def __repr__(self):
        return '<{} {}>'.format(self.__class__.__name__, self)

    def __str__(self):
        result = []
        render_pos_only_separator = False
        render_kw_only_separator = True
        for param in self.parameters.values():
            formatted = str(param)

            kind = param.kind

            if kind == _POSITIONAL_ONLY:
                render_pos_only_separator = True
            elif render_pos_only_separator:
                # It's not a positional-only parameter, and the flag
                # is set to 'True' (there were pos-only params before.)
                result.append('/')
                render_pos_only_separator = False

            if kind == _VAR_POSITIONAL:
                # OK, we have an '*args'-like parameter, so we won't need
                # a '*' to separate keyword-only arguments
                render_kw_only_separator = False
            elif kind == _KEYWORD_ONLY and render_kw_only_separator:
                # We have a keyword-only parameter to render and we haven't
                # rendered an '*args'-like parameter before, so add a '*'
                # separator to the parameters list ("foo(arg1, *, arg2)" case)
                result.append('*')
                # This condition should be only triggered once, so
                # reset the flag
                render_kw_only_separator = False

            result.append(formatted)

        if render_pos_only_separator:
            # There were only positional-only parameters, hence the
            # flag was not reset to 'False'
            result.append('/')

        rendered = '({})'.format(', '.join(result))

        if self.return_annotation is not _empty:
            anno = formatannotation(self.return_annotation)
            rendered += ' -> {}'.format(anno)

        return rendered


def signature(obj, follow_wrapped=True):
    """Get a signature object for the passed callable."""
    return Signature.from_callable(obj, follow_wrapped=follow_wrapped)