Set polar plot to have 0 degrees at the top

I have created a simple polar plot using matplotlib. I'm trying to make the plot with 0 degrees at the top (12 o'clock position) rather 开发者_如何学Gothan the right-hand side (3 o'clock position). I can't see any simple way to do this in the matplotlib documentation.

I've found an older question here on StackOverflow, but the accepted answer doesn't seem to work, and as it's over a year old I thought there may be a better way to do it now.

Any ideas?

Replace angle with angle - pi/4?