new_contents: import re
  
  from gmpy_cffi import version, mp_version, mpfr_version, mpc_version
  
  
  class TestVersion:
      def test_version(self):
          s = version()
          assert isinstance(s, str)
          assert re.match(r'\d\.\d\.\d', s)
  
      def test_mp_version(self):
          s = mp_version()
          assert isinstance(s, str)
          assert s.startswith('GMP ')
  
      def test_mpfr_version(self):
          s = mpfr_version()
          assert isinstance(s, str)
          assert s.startswith('MPFR ')
  
      def test_mpc_version(self):
          s = mpc_version()
          assert isinstance(s, str)
          assert s.startswith('MPC ')
  
subject: add test_version