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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 _fit_invhashing_union(vec_union, docs):
 # type: (FeatureUnion, Any) -> FeatureUnion """ Fit InvertableHashingVectorizer on doc inside a FeatureUnion. """

    return FeatureUnion(
        [(name, invert_hashing_and_fit(v, docs))
         for name, v in vec_union.transformer_list],
        transformer_weights=vec_union.transformer_weights,
        n_jobs=vec_union.n_jobs)