$ cat weirdimport.py 
from __future__ import (absolute_import, division,
                        unicode_literals)

print 3
$ futurize weirdimport.py 
RefactoringTool: Skipping optional fixer: idioms
RefactoringTool: Skipping optional fixer: ws_comma
Traceback (most recent call last):
  File ".../bin/futurize", line 9, in <module>
    load_entry_point('future==0.15.2', 'console_scripts', 'futurize')()
  File ".../site-packages/future-0.15.2-py2.7.egg/libfuturize/main.py", line 293, in main
    options.processes)
  File ".../lib2to3/refactor.py", line 706, in refactor
    items, write, doctests_only)
  File ".../lib2to3/refactor.py", line 301, in refactor
    self.refactor_file(dir_or_file, write, doctests_only)
  File ".../lib2to3/refactor.py", line 747, in refactor_file
    *args, **kwargs)
  File ".../lib2to3/refactor.py", line 354, in refactor_file
    tree = self.refactor_string(input, filename)
  File ".../lib2to3/refactor.py", line 386, in refactor_string
    self.refactor_tree(tree, name)
  File ".../lib2to3/refactor.py", line 460, in refactor_tree
    new = fixer.transform(node, results)
  File ".../site-packages/future-0.15.2-py2.7.egg/libfuturize/fixes/fix_print_with_import.py", line 20, in transform
    future_import(u'print_function', node)
  File ".../site-packages/future-0.15.2-py2.7.egg/libfuturize/fixer_util.py", line 210, in future_import
    names = check_future_import(node)
  File ".../site-packages/future-0.15.2-py2.7.egg/libfuturize/fixer_util.py", line 426, in check_future_import
    assert False, "strange import: %s" % savenode
AssertionError: strange import: from __future__ import (absolute_import, division,
                        unicode_literals)

$ futurize --version
0.15.2