def __sub__(self, entry):
        """
        Substracts an entry or collection of entries to an instance.
        """
        if type(entry).__name__ in TEXT_TYPE_LIST:
            self.collection.remove(entry)
        else:
            self.collection = self.collection.difference(entry)

        return self
def __sub__ ( self , entry ) : if type ( entry ) . __name__ in TEXT_TYPE_LIST : self . collection . remove ( entry ) else : self . collection = self . collection . difference ( entry ) return self
Substracts an entry or collection of entries to an instance.