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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, data_access=None):
 """Run the class validations against the instance. If the validations require database access, pass in a DataAccess derived instance. """

    self.clear_errors()
    self.before_validation()
    self.validator.validate(self, data_access)
    return not self.has_errors