For some reason this file crashes with

Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/nose/case.py", line 197, in runTest
    self.test(*self.arg)
  File "/home/marcink/DEV_git/python/python-modernize/tests/test_future_behaviour.py", line 92, in test_problematic_file
    _check_on_input(prb_content)
  File "/home/marcink/DEV_git/python/python-modernize/tests/test_future_behaviour.py", line 49, in _check_on_input
    modernize_main(extra_flags + ["-w", test_input_name])
  File "/home/marcink/DEV_git/python/python-modernize/libmodernize/main.py", line 117, in main
    options.processes)
  File "/usr/lib64/python2.7/lib2to3/refactor.py", line 706, in refactor
    items, write, doctests_only)
  File "/usr/lib64/python2.7/lib2to3/refactor.py", line 301, in refactor
    self.refactor_file(dir_or_file, write, doctests_only)
  File "/usr/lib64/python2.7/lib2to3/refactor.py", line 747, in refactor_file
    *args, **kwargs)
  File "/usr/lib64/python2.7/lib2to3/refactor.py", line 354, in refactor_file
    tree = self.refactor_string(input, filename)
  File "/usr/lib64/python2.7/lib2to3/refactor.py", line 386, in refactor_string
    self.refactor_tree(tree, name)
  File "/usr/lib64/python2.7/lib2to3/refactor.py", line 460, in refactor_tree
    new = fixer.transform(node, results)
  File "/home/marcink/DEV_git/python/python-modernize/libmodernize/fixes/fix_print.py", line 73, in transform
    add_future(node, u'print_function')
  File "/home/marcink/DEV_git/python/python-modernize/libmodernize/__init__.py", line 51, in add_future
    names = check_future_import(node)
  File "/home/marcink/DEV_git/python/python-modernize/libmodernize/__init__.py", line 18, in check_future_import
    node.children[1].value == u'__future__'):
AttributeError: 'Node' object has no attribute 'value'
This still fails
Simplified test to the extreme (likely)
Resolved second crash. Debugging showed, that in this very case (from
a.b.c. import d) node.children[1] was itself a node with children (and
without value)