英文文档: help([object]) Invoke the built-in help system. (This function is intended for interactive use.) If no argument is given, the interactive help system starts on the interpreter console. If the argument is a string, then the string is looked up a…
英文文档: class slice(stop) class slice(start, stop[, step]) Return a slice object representing the set of indices specified by range(start, stop, step). The start and steparguments default to None. Slice objects have read-only data attributes start, sto…