code: def get_element_masses(self):
          
  
          result = [0] * len(self.material.elements)
          for compound in self.material.compounds:
              c = self.get_compound_mass(compound)
              f = [c * x for x in emf(compound, self.material.elements)]
              result = [v+f[ix] for ix, v in enumerate(result)]
  
          return result
docs: Get the masses of elements in the package.
  
          :returns: [kg] An array of element masses. The sequence of the elements
            in the result corresponds with the sequence of elements in the
            element list of the material.