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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 bake(self, start_response):
 """Bakes the response and returns the content. Args: start_response (:obj:`callable`):
 Callback method that accepts status code and a list of tuples (pairs) containing headers' key and value respectively. """

        if isinstance(self._content, six.text_type):
            self._content = self._content.encode('utf8')

        if self._content_length is None:
            self._content_length = len(self._content)

        self._headers[HttpResponseHeaders.CONTENT_LENGTH] = \
            str(self._content_length)
        headers = list(self._headers.items())
        cookies = [(HttpResponseHeaders.SET_COOKIE, v.OutputString())
                   for _, v in self._cookies.items()]

        if len(cookies):
            headers = list(headers) + cookies
        start_response(self._status_code, headers)

        if isinstance(self._content, six.binary_type):
            return [self._content]

        return self._content