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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 Validate(self, problems, validate_children=True):
 """Validate attributes of this object. Check that this object has all required values set to a valid value without reference to the rest of the schedule. If the _schedule attribute is set then check that references such as route_id and service_id are correct. Args: problems: A ProblemReporter object validate_children: if True and the _schedule attribute is set than call ValidateChildren """

    self.ValidateRouteId(problems)
    self.ValidateServicePeriod(problems)
    self.ValidateDirectionId(problems)
    self.ValidateTripId(problems)
    self.ValidateShapeIdsExistInShapeList(problems)
    self.ValidateRouteIdExistsInRouteList(problems)
    self.ValidateServiceIdExistsInServiceList(problems)
    self.ValidateBikesAllowed(problems)
    self.ValidateWheelchairAccessible(problems)
    if self._schedule and validate_children:
      self.ValidateChildren(problems)