Literal strings concatenation#

Python has very convenient functionality — literal strings concatenation

In [1]: s = ('Test' 'String')

In [2]: s
Out[2]: 'TestString'

In [3]: s = 'Test' 'String'

In [4]: s
Out[4]: 'TestString'

You can even wrap parts of a line on different lines, but only if they are in parentheses:

In [5]: s = ('Test'
   ...: 'String')

In [6]: s
Out[6]: 'TestString'

This is very convenient to use in regex:

regex = (
    '(\S+) +(\S+) +'
    '\w+ +\w+ +'
    '(up|down|administratively down) +'

This way, the regex can be split and made easier to understand. Plus you can add explanatory comments in strings.

regex = (
    '(\S+) +(\S+) +' # interface and IP
    '\w+ +\w+ +'
    '(up|down|administratively down) +' # Status
    '(\w+)' # Protocol

It is also convenient to use this technique when writing a long message:

In [7]: message = ('During command execution "{}" '
   ...: 'such error occured "{}".\n'
   ...: 'Exclude this command from the list? [y/n]')

In [8]: message
Out[8]: 'During command execution "{}" such error occured "{}".\nExclude this command from the list? [y/n]'