Code review comment for lp:~jcsackett/launchpad/private-team-to-private-team-519306

Looks good Jon with these comments:

1) use httplib.BAD_REQUEST instead of a raw 400 throughout your changes. Please leave the comment that shows the raw number.

2) run utilities/format-imports on your changed files. Easier than me pointing out the issues.

3) 'e' is a pretty recognized variable for an exception but we still try to avoid one letter variables, save for i,j,k loop variables.