def isprime_timing ( n ):

  from sympy import isprime
  from time import perf_counter

  tic = perf_counter ( )      # Start the clock.

  is_prime = isprime ( n )

  toc = perf_counter ( )     # Stop the clock.

  print ( 'isprime(): is ', n, ' prime? ', is_prime )
  print ( '  Computing seconds was ', toc - tic )