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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 geoid(self):
 """"Return first child of the column, or self that is marked as a geographic identifier"""


        if self.valuetype_class.is_geoid():
            return self

        for c in self.table.columns:
            if c.parent == self.name and  c.valuetype_class.is_geoid():
                return c