code: def sha1_hash(string):
      '''
      Return the SHA1 of the input string.
      '''
  
      hasher = sha1()
      hasher.update(string.encode())
      return hasher.hexdigest(f sha1_hash(string):
      '''
      Return the SHA1 of the input string.
      '''
  
      hasher = sha1()
      hasher.update(string.encode())
      return hasher.hexdigest()
docs: Return the SHA1 of the input string.