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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 check_hints(self, reply):
 """Parse the hints to check for errors. """

        try:
            f_ind = reply.index("hints")
            l_ind = reply.rindex("hints")
        except Exception:
            fail_reason = vdp_const.hints_failure_reason % (reply)
            LOG.error("%s", fail_reason)
            return False, fail_reason
        if f_ind != l_ind:
            # Currently not supported if reply contains a filter keyword
            fail_reason = vdp_const.multiple_hints_failure_reason % (reply)
            LOG.error("%s", fail_reason)
            return False, fail_reason
        try:
            hints_compl = reply.partition("hints")[2]
            hints_val = reply.partition("hints")[2][0:4]
            len_hints = int(hints_val)
            hints_val = hints_compl[4:4 + len_hints]
            hints = int(hints_val)
            if hints != 0:
                fail_reason = vdp_const.nonzero_hints_failure % (hints)
                return False, fail_reason
        except ValueError:
            fail_reason = vdp_const.format_failure_reason % (reply)
            LOG.error("%s", fail_reason)
            return False, fail_reason
        return True, None