input: Write a python function to remove all occurrences of the word "the" from a string.
  assert remove_the("the quick brown fox jumped over the lazy dog") == " quick brown fox jumped over  lazy dog"
  assert remove_the("the the the") == "  "
  assert remove_the("The quick brown fox") == "The quick brown fox"
output: def remove_the(input_string):
      return ' '.join(word for word in input_string.split() if word.lower() != 'the')