<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def verify_checksum(self):
 """ Verify the checksum in the header for this HDU. """

        res = self._FITS.verify_checksum(self._ext+1)
        if res['dataok'] != 1:
            raise ValueError("data checksum failed")
        if res['hduok'] != 1:
            raise ValueError("hdu checksum failed")