input: Write a python function that takes a list of strings and returns a new list with each string reversed.
  assert reverse_strings(['Red', 'Green', 'Blue', 'White', 'Black'])==['deR', 'neerG', 'eulB', 'etihW', 'kcalB']
  assert reverse_strings(['john','amal','joel','george'])==['nhoj','lama','leoj','egroeg']
  assert reverse_strings(['jack','john','mary'])==['kcaj','nhoj','yram']
output: def reverse_strings(strings):
      return [s[::-1] for s in strings]