def read_bytes ( fo , writer_schema = None , reader_schema = None ) : size = read_long ( fo ) return fo . read ( size )
maximum size of a bytes object python
Bytes are encoded as a long followed by that many bytes of data .
def read_bytes(fo, writer_schema=None, reader_schema=None):
    """Bytes are encoded as a long followed by that many bytes of data."""
    size = read_long(fo)
    return fo.read(size)