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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_top_header(self):
 """Read the header text and number of reference seqs"""

    magic = self._fh.read(4)
    l_text = struct.unpack('<i',self._fh.read(4))[0]
    header_text = self._fh.read(l_text).rstrip('\0')
    n_ref = struct.unpack('<i',self._fh.read(4))[0]
    return header_text, n_ref