code: def from_pseudoinverse(cls, strains, stresses):
          
          # convert the stress/strain to Nx6 arrays of voigt-notation
          warnings.warn("Pseudoinverse fitting of Strain/Stress lists may yield "
                        "questionable results from vasp data, use with caution.")
          stresses = np.array([Stress(stress).voigt for stress in stresses])
          with warnings.catch_warnings(record=True):
              strains = np.array([Strain(strain).voigt for strain in strains])
  
          voigt_fit = np.transpose(np.dot(np.linalg.pinv(strains), stresses))
          return cls.from_voigt(voigt_fit)
docs: Class method to fit an elastic tensor from stress/strain
          data.  Method uses Moore-Penrose pseudoinverse to invert
          the s = C*e equation with elastic tensor, stress, and
          strain in voigt notation
  
          Args:
              stresses (Nx3x3 array-like): list or array of stresses
              strains (Nx3x3 array-like): list or array of strains