swift234

[gardening] Fix violations of non-controversial PEP8 rules

Fixes:
* multiple statements on one line (colon) (E701)
* missing whitespace around arithmetic operator (E226)
* missing whitespace around operator (E225)
* closing bracket does not match visual indentation (E124)
* blank line contains whitespace (W293)
* continuation line missing indentation or outdented (E122)
* continuation line over-indented for hanging indent (E126)
* missing expected blank line (E301)
* trailing whitespace (W291)
* unexpected spaces around keyword / parameter equals (E251)
* whitespace after '(', '[' or '{' (E201)
* whitespace before ')', ']' or '}' (E202)
* whitespace before ',' or ':' (E203)