Removed deprecated command from main.py line 477 and two PEP8 violations
Removed deprecated command from main.py line 477 and two PEP8 violations

mitocw/latex2edx,evheubel/latex2edx,jefrench/latex2edx,mitocw/latex2edx,mitocw/latex2edx,evheubel/latex2edx,jefrench/latex2edx,jefrench/latex2edx,evheubel/latex2edx