python - Concise way to split a string into a list of fixed number of tokens -

i writing piece of code needs split hyphen delimited string @ 3 tokens. if there less 3 tokens after splitting, should append sufficient number of empty strings in order make 3 tokens.

for example, 'foo-bar-baz' should split ['foo', 'bar', 'baz'], foo-bar should split ['foo', 'bar', ''].

here code wrote.

def three_tokens(s):     tokens = s.split('-', 2)     if len(tokens) == 1:         tokens.append('')         tokens.append('')     elif len(tokens) == 2:         tokens.append('')     return tokens  print(three_tokens('')) print(three_tokens('foo')) print(three_tokens('foo-bar')) print(three_tokens('foo-bar-baz')) print(three_tokens('foo-bar-baz-qux')) 

here output:

['', '', ''] ['foo', '', ''] ['foo', 'bar', ''] ['foo', 'bar', 'baz'] ['foo', 'bar', 'baz-qux'] 

my question three_tokens function have written seems verbose little task. there pythonic way write this, or there python function or class meant kind of task makes code more concise?

you use simple while loop:

def three_tokens(s):     tokens = s.split('-', 2)     while len(tokens) < 3:         tokens.append('')     return tokens 

or extend list calculated number of empty strings:

def three_tokens(s):     tokens = s.split('-', 2)     tokens.extend([''] * (3 - len(tokens)))     return tokens 

or use concatenation can put in return statement:

def three_tokens(s):     tokens = s.split('-', 2)     return tokens + [''] * (3 - len(tokens))