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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 change_group(self, name, group):
 		"""Change the group of a host given the name of the host. 		@type name: str 		@type group: str 		"""

		m1 = OmapiMessage.open(b"host")
		m1.update_object(dict(name=name))
		r1 = self.query_server(m1)
		if r1.opcode != OMAPI_OP_UPDATE:
			raise OmapiError("opening host %s failed" % name)
		m2 = OmapiMessage.update(r1.handle)
		m2.update_object(dict(group=group))
		r2 = self.query_server(m2)
		if r2.opcode != OMAPI_OP_UPDATE:
			raise OmapiError("changing group of host %s to %s failed" % (name, group))