I am not a native English speaker. When I code with Python, I often make spelling mistakes and get 'NameError' Exceptions. Unit test can solve some problems but not all. Because one can hardly construct test cases which cover all logic. So I think a tool that detect such errors would help me a lot but I searched Google and cannot find it.
You could get an IDE which helps a bit with autocompletion of names, though not in all situations. PyDev is one such IDE with autocompletion; PyCharm is another (not free).
Using autocomplete is probably your best bet to solve your problem in the long term. Even if you find a tool which attempts to correct such spelling errors, that will not solve the initial problem and will probably just cause new ones.
Does there  a tool exists which can help programmer avoid Python NameError?