Reads a given number of characters from the response.

        :param size: The number of characters to read, or "None" to read the
            entire response.
        :type size: ``integer`` or "None"

def read(self, size = None):
        """Reads a given number of characters from the response.

        :param size: The number of characters to read, or "None" to read the
            entire response.
        :type size: ``integer`` or "None"

        """
        r = self._buffer
        self._buffer = bytes()
        if size is not None:
            size -= len(r)
        r = r + self._response.read(size)
        #raise RuntimeError
        return r