text: import pySPM
  import unittest
  
  class TestElts(unittest.TestCase):
  
      def test_basic(self):
          assert pySPM.utils.simplify_formula("H^29SiH") == "H2^29Si"
          assert pySPM.utils.get_mass("C") == 12
          assert pySPM.utils.is_main_isotope("C", 12)
          assert not pySPM.utils.is_main_isotope("C", 13)
  
  if __name__ == "__main__":
      unittest.main()