code: def expectation_sensitivity(T, a):
      r
      # check input
      T = _types.ensure_ndarray_or_sparse(T, ndim=2, uniform=True, kind='numeric')
      a = _types.ensure_float_vector(a, require_order=True)
      # go
      if _issparse(T):
          _showSparseConversionWarning()
          return dense.sensitivity.expectation_sensitivity(T.toarray(), a)
      else:
          return dense.sensitivity.expectation_sensitivity(T, a)
docs: r"""Sensitivity of expectation value of observable A=(a_i).
  
      Parameters
      ----------
      T : (M, M) ndarray
          Transition matrix
      a : (M,) ndarray
          Observable, a[i] is the value of the observable at state i.
  
      Returns
      -------
      S : (M, M) ndarray
          Sensitivity matrix of the expectation value.