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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 references(self, env, object_name, model, assoc_class, result_class_name, role, result_role, keys_only):
 """Instrument Associations. All four association-related operations (Associators, AssociatorNames, References, ReferenceNames) are mapped to this method. This method is a python generator Keyword arguments: env -- Provider Environment (pycimmb.ProviderEnvironment) object_name -- A pywbem.CIMInstanceName that defines the source CIM Object whose associated Objects are to be returned. model -- A template pywbem.CIMInstance to serve as a model of the objects to be returned. Only properties present on this model need to be set. assoc_class -- The pywbem.CIMClass. result_class_name -- If not empty, this string acts as a filter on the returned set of Instances by mandating that each returned Instances MUST represent an association between object_name and an Instance of a Class whose name matches this parameter or a subclass. role -- If not empty, MUST be a valid Property name. It acts as a filter on the returned set of Instances by mandating that each returned Instance MUST refer to object_name via a Property whose name matches the value of this parameter. result_role -- If not empty, MUST be a valid Property name. It acts as a filter on the returned set of Instances by mandating that each returned Instance MUST represent associations of object_name to other Instances, where the other Instances play the specified result_role in the association (i.e. the name of the Property in the Association Class that refers to the Object related to object_name MUST match the value of this parameter). keys_only -- A boolean. True if only the key properties should be set on the generated instances. The following diagram may be helpful in understanding the role, result_role, and result_class_name parameters. | object_name.classname | | result_class_name | | ~~~~~~~~~~~~~~~~~~~~~ | | ~~~~~~~~~~~~~~~~~ | | | [Association] assoc_class | | | object_name | ~~~~~~~~~~~~~~~~~~~~~~~~~ | | (CIMInstanceName) | result_class_name REF result_role +------+ | |(CIMInstanceName) Possible Errors: CIM_ERR_ACCESS_DENIED CIM_ERR_NOT_SUPPORTED CIM_ERR_INVALID_NAMESPACE CIM_ERR_INVALID_PARAMETER (including missing, duplicate, unrecognized or otherwise incorrect parameters) CIM_ERR_FAILED (some other unspecified error occurred) """

        pass