Unnecessary install_aliases when on list_object.append()

[alexlambson]

In my code I have an area that calls

commands = []

commands.append("blahblahblah")

The .appends() is triggering futurize to import standard_library and call install_aliases
However, I can not do this where I work because it borks a lot of things.

Is there a reason why .appends(), .extends(), etc is triggering this that I am not aware of?

I got around the complaint by using

commands += ["blahblahblah"]

[ucodery]

I am not sure if this warrants a new issue, but the same thing happens if the phrase 'thread.join' appears in a file, even if that file is not using the library thread or threading.

A simple repro

+21:33:57 highland@basecamp:~/tmp$ for f in future/*; do printf "\t==$f\n" && cat $f; done
        ==future/a.py
thread.join()
        ==future/b.py
thread
        ==future/c.py
Thread.join()
        ==future/d.py
'foo'.join([])
+21:34:08 highland@basecamp:~/tmp$ futurize -f libfuturize.fixes.fix_future_standard_library future/
root: Generating grammar tables from /usr/lib/python2.7/lib2to3/PatternGrammar.txt
RefactoringTool: Refactored future/a.py
--- future/a.py (original)
+++ future/a.py (refactored)
@@ -1 +1,3 @@
+from future import standard_library
+standard_library.install_aliases()
 thread.join()
RefactoringTool: Files that need to be modified:
RefactoringTool: future/a.py```