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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, obj):
 """Base validation method. Will inspect class attributes to dermine just what should be present"""

        if 'tags' in obj and not isinstance(obj['tags'], list):
            raise aomi_excep.Validation('tags must be a list')

        if self.present:
            check_obj(self.required_fields, self.name(), obj)