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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 HasDateExceptionOn(self, date, exception_type=_EXCEPTION_TYPE_ADD):
 """Test if this service period has a date exception of the given type. Args: date: a string of form "YYYYMMDD" exception_type: the exception type the date should have. Defaults to _EXCEPTION_TYPE_ADD Returns: True iff this service has service exception of specified type at date. """

    if date in self.date_exceptions:
      return exception_type == self.date_exceptions[date][0]
    return False