That is a bit of a hack though ;). You could also do it with %-style formatting as well:

  some_var = ...
  "%(some_var)s" % locals()

If you want to do both locals and globals you can do:

  some_var = ...
  "%(some_var)s" % dict(globals(), **locals())

New Python versions (>=3.5) have this syntax:

  "%(some_var)s" % {**globals(), **locals()}

But those versions also have f-strings so that's sort of moot.