Fix flake8 warnings and errors

[chocoelho]

https://bpaste.net/show/e68638501acb

[chocoelho]

https://www.python.org/dev/peps/pep-0008/

[chocoelho]

I'd priorize if one wants to get familiar with some part of the project:

• 1 E901 SyntaxError: invalid syntax
• 2 W601 .has_key() is deprecated, use 'in'
• 4 W602 deprecated form of raising exception
• 5 E713 test for membership should be 'not in'
• 8 E711 comparison to None should be 'if cond is None:'
• 11 E712 comparison to True should be 'if cond is True:' or 'if cond:'

If one wants to filter the error, one might execute the following example command:

flake8 --select=error_code folder_or_file_to_examine

e.g, if one wants to know if there are any deprecated form of raising exception

flake8 --select=W602 folder_or_file_to_examine

[chocoelho]

Packages that must be given attention:

• client
• schedule
• careprofessional
• person
• place
• referral