input: Write a python function to split a string on whitespace.
  assert splitOnWhitespace("Python is an interpreted language.") == ['Python', 'is', 'an', 'interpreted', 'language.']
  assert splitOnWhitespace("Test the function with some input.") == ['Test', 'the', 'function', 'with', 'some', 'input.']
  assert splitOnWhitespace("   Leading and trailing spaces    ") == ['Leading', 'and', 'trailing', 'spaces']
output: def splitOnWhitespace(s):
      return s.split()