Conditionally including additional characters using python string formatting

Question

Is it possible using python's string format to conditionally include additional characters along with the string variable only if the variable is not empty?

>>> format_string = "{last}, {first}"
>>> name = {'first': 'John', 'last':'Smith'}
>>> format_string.format(**name)
'Smith, John' # great!
>>> name = {'first': 'John', 'last':''}
>>> format_string.format(**name)
', John' # don't want the comma and space here, just 'John'

I would like to use the sameformat_string variable to handle any combination of empty or non-empty values for first or last in the name dict.

What's the easiest way to do this in python?

Answer 1

Why don't you use strip():

>>> format_string = "{last}, {first}"
>>> name = {'first': 'John', 'last':''}
>>> format_string.format(**name).strip(', ')
>>> 'John'