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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 _invalid_indexer(self, form, key):
 """ Consistent invalid indexer message. """

        raise TypeError("cannot do {form} indexing on {klass} with these "
                        "indexers [{key}] of {kind}".format(
                            form=form, klass=type(self), key=key,
                            kind=type(key)))