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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 parse_split(cls, header: bytes, body: bytes) -> 'MessageContent': """Parse the header and body bytestrings into message content. Args: header: The header bytestring to parse. body: The body bytestring to parse. """

        header_lines = cls._find_lines(header)
        body_lines = cls._find_lines(body)
        header_view = memoryview(header)
        body_view = memoryview(body)
        return cls._parse_split([header_view, body_view], header, body,
                                header_view, body_view,
                                header_lines, body_lines)