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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 create_namespace(self, namespace):
 """ Create the specified CIM namespace in the WBEM server and update this WBEMServer object to reflect the new namespace there. This method attempts the following approaches for creating the namespace, in order, until an approach succeeds: 1. Namespace creation as described in the WBEM Server profile (:term:`DSP1092`) via CIM method `CIM_WBEMServer.CreateWBEMServerNamespace()`. This is a new standard approach that is not likely to be widely implemented yet. 2. Issuing the `CreateInstance` operation using the CIM class representing namespaces ('PG_Namespace' for OpenPegasus, and 'CIM_Namespace' otherwise), against the Interop namespace. This approach is typically supported in WBEM servers that support the creation of CIM namespaces. This approach is similar to the approach described in :term:`DSP0200`. Creating namespaces using the `__Namespace` pseudo-class has been deprecated already in DSP0200 1.1.0 (released in 01/2003), and pywbem does not implement that approach. Parameters: namespace (:term:`string`):
 CIM namespace name. Must not be `None`. The namespace may contain leading and a trailing slash, both of which will be ignored. Returns: :term:`unicode string`: The specified CIM namespace name in its standard format (i.e. without leading or trailing slash characters). Raises: Exceptions raised by :class:`~pywbem.WBEMConnection`. ModelError: An issue with the model implemented by the WBEM server. CIMError: CIM_ERR_ALREADY_EXISTS, Specified namespace already exists in the WBEM server. CIMError: CIM_ERR_NOT_FOUND, Interop namespace could not be determined. CIMError: CIM_ERR_NOT_FOUND, Unexpected number of `CIM_ObjectManager` instances. CIMError: CIM_ERR_FAILED, Unexpected number of central instances of WBEM Server profile. """


        std_namespace = _ensure_unicode(namespace.strip('/'))

        ws_profiles = self.get_selected_profiles('DMTF', 'WBEM Server')
        if ws_profiles:

            # Use approach 1: Method defined in WBEM Server profile

            ws_profiles_sorted = sorted(
                ws_profiles, key=lambda prof: prof['RegisteredVersion'])
            ws_profile_inst = ws_profiles_sorted[-1]  # latest version
            ws_insts = self.get_central_instances(ws_profile_inst.path)
            if len(ws_insts) != 1:
                raise CIMError(
                    CIM_ERR_FAILED,
                    _format("Unexpected number of central instances of WBEM "
                            "Server profile: {0!A}",
                            [i.path for i in ws_insts]))
            ws_inst = ws_insts[0]

            ns_inst = CIMInstance('CIM_WBEMServerNamespace')
            ns_inst['Name'] = std_namespace

            try:
                (ret_val, out_params) = self._conn.InvokeMethod(
                    MethodName="CreateWBEMServerNamespace",
                    ObjectName=ws_inst.path,
                    Params=[('NamespaceTemplate', ns_inst)])
            except CIMError as exc:
                if exc.status_code in (CIM_ERR_METHOD_NOT_FOUND,
                                       CIM_ERR_METHOD_NOT_AVAILABLE,
                                       CIM_ERR_NOT_SUPPORTED):
                    # Method is not implemented.
                    # CIM_ERR_NOT_SUPPORTED is not an official status code for
                    # this situation, but is used by some implementations.
                    pass  # try next approach
                else:
                    raise
            else:
                if ret_val != 0:
                    raise CIMError(
                        CIM_ERR_FAILED,
                        _format("The CreateWBEMServerNamespace() method is "
                                "implemented but failed: {0}",
                                out_params['Errors']))

        else:

            # Use approach 2: CreateInstance of CIM class for namespaces

            # For OpenPegasus, use 'PG_Namespace' class to account for issue
            # when using 'CIM_Namespace'. See OpenPegasus bug 10112:
            # https://bugzilla.openpegasus.org/show_bug.cgi?id=10112
            if self.brand == "OpenPegasus":
                ns_classname = 'PG_Namespace'
            else:
                ns_classname = 'CIM_Namespace'

            ns_inst = CIMInstance(ns_classname)

            # OpenPegasus requires this property to be True, in order to
            # allow schema updates in the namespace.
            if self.brand == "OpenPegasus":
                ns_inst['SchemaUpdatesAllowed'] = True

            ns_inst['Name'] = std_namespace

            # DSP0200 is not clear as to whether just "Name" or all key
            # properties need to be provided. For now, we provide all key
            # properties.
            # OpenPegasus requires all key properties, and it re-creates the
            # 5 key properties besides "Name" so that the returned instance
            # path may differ from the key properties provided.

            ns_inst['CreationClassName'] = ns_classname
            ns_inst['ObjectManagerName'] = self.cimom_inst['Name']
            ns_inst['ObjectManagerCreationClassName'] = \
                self.cimom_inst['CreationClassName']
            ns_inst['SystemName'] = self.cimom_inst['SystemName']
            ns_inst['SystemCreationClassName'] = \
                self.cimom_inst['SystemCreationClassName']

            self.conn.CreateInstance(ns_inst, namespace=self.interop_ns)

        # Refresh the list of namespaces in this object to include the one
        # we just created.
        # Namespace creation is such a rare operation that we can afford
        # the extra namespace determination operations, to make sure we
        # really have the new namespace.
        self._determine_namespaces()

        return std_namespace