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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 EnumerateClassNames(self, namespace=None, ClassName=None, DeepInheritance=None, **extra):
 # pylint: disable=invalid-name,line-too-long """ Enumerate the names of subclasses of a class, or of the top-level classes in a namespace. This method performs the EnumerateClassNames operation (see :term:`DSP0200`). See :ref:`WBEM operations` for a list of all methods performing such operations. If the operation succeeds, this method returns. Otherwise, this method raises an exception. Parameters: namespace (:term:`string`):
 Name of the namespace in which the class names are to be enumerated (case independent). Leading and trailing slash characters will be stripped. The lexical case will be preserved. If `None`, the namespace of the `ClassName` parameter will be used, if specified as a :class:`~pywbem.CIMClassName` object. If that is also `None`, the default namespace of the connection will be used. ClassName (:term:`string` or :class:`~pywbem.CIMClassName`):
 Name of the class whose subclasses are to be retrieved (case independent). If specified as a :class:`~pywbem.CIMClassName` object, its host attribute will be ignored. If `None`, the top-level classes in the namespace will be retrieved. DeepInheritance (:class:`py:bool`):
 Indicates that all (direct and indirect) subclasses of the specified class or of the top-level classes are to be included in the result, as follows: * If `False`, only direct subclasses of the specified class or only top-level classes are included in the result. * If `True`, all direct and indirect subclasses of the specified class or the top-level classes and all of their direct and indirect subclasses are included in the result. * If `None`, this parameter is not passed to the WBEM server, and causes the server-implemented default to be used. :term:`DSP0200` defines that the server-implemented default is `False`. Note, the semantics of the `DeepInheritance` parameter in :meth:`~pywbem.WBEMConnection.EnumerateInstances` is different. **extra : Additional keyword arguments are passed as additional operation parameters to the WBEM server. Note that :term:`DSP0200` does not define any additional parameters for this operation. Returns: A list of :term:`unicode string` objects that are the class names of the enumerated classes. Raises: Exceptions described in :class:`~pywbem.WBEMConnection`. """


        exc = None
        classnames = None
        method_name = 'EnumerateClassNames'

        if self._operation_recorders:
            self.operation_recorder_reset()
            self.operation_recorder_stage_pywbem_args(
                method=method_name,
                namespace=namespace,
                ClassName=ClassName,
                DeepInheritance=DeepInheritance,
                **extra)

        try:

            stats = self.statistics.start_timer(method_name)
            if namespace is None and isinstance(ClassName, CIMClassName):
                namespace = ClassName.namespace
            namespace = self._iparam_namespace_from_namespace(namespace)
            classname = self._iparam_classname(ClassName, 'ClassName')

            result = self._imethodcall(
                method_name,
                namespace,
                ClassName=classname,
                DeepInheritance=DeepInheritance,
                **extra)

            if result is None:
                classpaths = []
            else:
                classpaths = result[0][2]

            classnames = []
            for classpath in classpaths:

                if not isinstance(classpath, CIMClassName):
                    raise CIMXMLParseError(
                        _format("Expecting CIMClassName object in result "
                                "list, got {0} object",
                                classpath.__class__.__name__),
                        conn_id=self.conn_id)

                # The EnumerateClassNames CIM-XML operation returns class
                # paths as CLASSNAME elements.
                # We want to return class names as strings.
                classnames.append(classpath.classname)

            return classnames

        except (CIMXMLParseError, XMLParseError) as exce:
            exce.request_data = self.last_raw_request
            exce.response_data = self.last_raw_reply
            exc = exce
            raise
        except Exception as exce:
            exc = exce
            raise
        finally:
            self._last_operation_time = stats.stop_timer(
                self.last_request_len, self.last_reply_len,
                self.last_server_response_time, exc)
            if self._operation_recorders:
                self.operation_recorder_stage_result(classnames, exc)