input: Write a function to remove all punctuations from the given string of sentences. If no punctuation exists in the string, the function should return the original string. If the input string is empty, the function should 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: powerful and simple!")=="Python powerful and simple"
  assert remove_punctuations("")==""
  assert remove_punctuations("NoPunctuation")=="NoPunctuation"
output: def remove_punctuations(s):
      import string
      return s.translate(str.maketrans('', '', string.punctuation))