Remove lint errors

[djmgit]

As of now there are plenty of lint errors in EP2. These errors needs to be fixed.

Steps

• Install dev dependencies using sudo pip3 install -r requirements-dev.txt
• open .flake8 file present at the root of the project.
• remove one rule from the ignore list.
• run flake8
• Solve the errors reported by flake8
• Open an issue for the rule you are fixing (one rule per issue)
• Refer this issue there
• Send a PR. In the PR too, refer this issue as parent.
• Comment that you are working on it.