Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/nix/store/rspyw301k7k68dh06sgyf1gbk1gw5zvd-python-2.7.18/lib/python2.7/py_compile.py", line 117, in compile
    raise py_exc
py_compile.PyCompileError: Sorry: IndentationError: expected an indented block (foo.py, line 2)

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