code: def AddNewSignature(self, pattern, offset=None):
      
      self.signatures.append(Signature(pattern, offset=offset))
docs: Adds a signature.
  
      Args:
        pattern (bytes): pattern of the signature.
        offset (int): offset of the signature. None is used to indicate
            the signature has no offset. A positive offset is relative from
            the start of the data a negative offset is relative from the end
            of the data.