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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 set_instance(self, env, instance, previous_instance, cim_class):
 """Return a newly created or modified instance. Keyword arguments: env -- Provider Environment (pycimmb.ProviderEnvironment) instance -- The new pywbem.CIMInstance. If modifying an existing instance, the properties on this instance have been filtered by the PropertyList from the request. previous_instance -- The previous pywbem.CIMInstance if modifying an existing instance. None if creating a new instance. cim_class -- The pywbem.CIMClass Return the new instance. The keys must be set on the new instance. Possible Errors: CIM_ERR_ACCESS_DENIED CIM_ERR_NOT_SUPPORTED CIM_ERR_INVALID_PARAMETER (including missing, duplicate, unrecognized or otherwise incorrect parameters) CIM_ERR_ALREADY_EXISTS (the CIM Instance already exists -- only valid if previous_instance is None, indicating that the operation was CreateInstance) CIM_ERR_NOT_FOUND (the CIM Instance does not exist -- only valid if previous_instance is not None, indicating that the operation was ModifyInstance) CIM_ERR_FAILED (some other unspecified error occurred) """

        raise pywbem.CIMError(pywbem.CIM_ERR_NOT_SUPPORTED, "")