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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 get_setter(self, oid):
 		""" 		Retrieve the nearest parent setter function for an OID 		"""

		if hasattr(self.setter, oid):
			return self.setter[oid]
		parents = [ poid for poid in list(self.setter.keys()) if oid.startswith(poid) ]
		if parents:
			return self.setter[max(parents)]
		return self.default_setter