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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 store(self, store=None, usage='both', mech=None, overwrite=False, set_default=False):
 """Store these credentials into the given store This method stores the current credentials into the specified credentials store. If the default store is used, support for :rfc:`5588` is required. Otherwise, support for the credentials store extension is required. :requires-ext:`rfc5588` or :requires-ext:`cred_store` Args: store (dict):
 the store into which to store the credentials, or None for the default store. usage (str):
 the usage to store the credentials with -- either 'both', 'initiate', or 'accept' mech (OID):
 the :class:`MechType` to associate with the stored credentials overwrite (bool):
 whether or not to overwrite existing credentials stored with the same name, etc set_default (bool):
 whether or not to set these credentials as the default credentials for the given store. Returns: StoreCredResult: the results of the credential storing operation Raises: GSSError ExpiredCredentialsError MissingCredentialsError OperationUnavailableError DuplicateCredentialsElementError """


        if store is None:
            if rcred_rfc5588 is None:
                raise NotImplementedError("Your GSSAPI implementation does "
                                          "not have support for RFC 5588")

            return rcred_rfc5588.store_cred(self, usage, mech,
                                            overwrite, set_default)
        else:
            if rcred_cred_store is None:
                raise NotImplementedError("Your GSSAPI implementation does "
                                          "not have support for manipulating "
                                          "credential stores directly")

            store = _encode_dict(store)

            return rcred_cred_store.store_cred_into(store, self, usage, mech,
                                                    overwrite, set_default)