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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 gather_parameters(self, request, response, context, api_version=None, **input_parameters):
 """Gathers and returns all parameters that will be used for this endpoint"""

        input_parameters.update(request.params)

        if self.parse_body and request.content_length:
            body = request.stream
            content_type, content_params = parse_content_type(request.content_type)
            body_formatter = body and self.inputs.get(content_type, self.api.http.input_format(content_type))
            if body_formatter:
                body = body_formatter(body, content_length=request.content_length, **content_params)
            if 'body' in self.all_parameters:
                input_parameters['body'] = body
            if isinstance(body, dict):
                input_parameters.update(body)
        elif 'body' in self.all_parameters:
            input_parameters['body'] = None

        if 'request' in self.all_parameters:
            input_parameters['request'] = request
        if 'response' in self.all_parameters:
            input_parameters['response'] = response
        if 'api_version' in self.all_parameters:
            input_parameters['api_version'] = api_version
        for parameter, directive in self.directives.items():
            arguments = (self.defaults[parameter], ) if parameter in self.defaults else ()
            input_parameters[parameter] = directive(*arguments, response=response, request=request,
                                                    api=self.api, api_version=api_version, context=context,
                                                    interface=self)
        return input_parameters