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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 _read_message(self):
 """Reads the contents of a message. Returns: body of message if parsable else None """

        line = self._rfile.readline()

        if not line:
            return None

        content_length = self._content_length(line)

        # Blindly consume all header lines
        while line and line.strip():
            line = self._rfile.readline()

        if not line:
            return None

        # Grab the body
        return self._rfile.read(content_length)