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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def signature(self):
 """Create a signature for this method, only in Python > 3.4"""

        if not use_signature:
            raise NotImplementedError("Python 3 only.")

        if self.static:
            parameters = \
                (Parameter(name='cls',
                           kind=Parameter.POSITIONAL_ONLY),)

        else:
            parameters = \
                (Parameter(name='self',
                           kind=Parameter.POSITIONAL_ONLY),)

        if self.input_transform:
            return signature(self.input_transform)

        if self.uses_request:
            fields = get_fields(self.request_type)
            if not self.static:
                if self.field_name not in fields:
                    raise NameError("field '{}' not found in {}".format(
                        self.field_name, self.request_name))
                fields.remove(self.field_name)
            parameters += tuple(
                Parameter(name=name, kind=Parameter.POSITIONAL_OR_KEYWORD,
                          default=None)
                for name in fields)

        return Signature(parameters)