input: Write a function to remove all punctuations from a given string. If the input string is empty, return an empty string.
  assert remove_punctuations("This is a sample string!")=="This is a sample string"
  assert remove_punctuations("Hello, World!")=="Hello World"
  assert remove_punctuations("Python is fun!")=="Python is fun"
  assert remove_punctuations("Testing: 1, 2, 3.")=="Testing 1 2 3"
  assert remove_punctuations("This is a test!")=="This is a test"
  assert remove_punctuations("")==""
output: def remove_punctuations(s):
      import string
      return s.translate(str.maketrans('', '', string.punctuation))