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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_data(self, fp_, header):
 """Read data block"""

        nlines = int(header["block2"]['number_of_lines'][0])
        ncols = int(header["block2"]['number_of_columns'][0])
        return da.from_array(np.memmap(self.filename, offset=fp_.tell(),
                                       dtype='<u2', shape=(nlines, ncols), mode='r'),
                             chunks=CHUNK_SIZE)