code: def _get_indices_and_signs(hasher, terms):
      
      X = _transform_terms(hasher, terms)
      indices = X.nonzero()[1]
      signs = X.sum(axis=1).A.ravel()
      return indices, signs
docs: For each term from ``terms`` return its column index and sign,
      as assigned by FeatureHasher ``hasher``.