PEP8 compliance, minor bug fix and invalid type value added to error output.

Hi,

I've been using this module for a while now, thanks for it. I have made a bunch of PEP8 compliance updates because my IDE was constantly reporting them to me and it was grabbing my attention. So mostly this pull request is PEP8 compliance updates.
There was one minor code error in unsubscribe where a bytearray class was assigned instead of an instance. 
Also I added the unknown/invalid type value to the output in situations where an invalid type has been received.

Regards,
Chris