Updates keep failing

What is the problem?
When I try to update octopi I keep getting this message:
You are using pip version 9.0.1, however version 9.0.3 is available.
You should consider upgrading via the 'pip install --upgrade pip' command

What did you already try to solve it?
I tried accessing the pi via PuTTY and running the command provided, but I get this error when I do that:
-bash: pip: command not found

It would help me out a lot if someone could tell me how to fix this, I'll try to check back regularly to reply to any comments

You don't have to update pip even though it can be really nagging about this.

If you really want to update pip, on OctoPi run ~/oprint/bin/pip install --upgrade pip.

If you don't have OctoPi but a manual install then run /path/to/OctoPrint/venv/bin/pip install --upgrade pip.

If pip is passed --disable-pip-version-check it will not display that message.

(more to Gina than OP)

@tedder42 I'm a bit undecided on whether adding that would be a good idea though. It would hide information that might be important for some people. I briefly thought about making it simply part of the update plugin so that you can update your pip through OctoPrint, but the problem with that is that I've run into issues with changed pip versions in the past (latest issue arose with 9.0.2 due to a change in internal that caused a version check to fail). Really tricky to decide what's best here.

Yeah, I know what you mean. And yeah, 9.0.2 burned me at $dayjob. At this point it seems pip is stable enough to just leave alone unless there are vulnerabilities discovered. And seeing a visible warning that can be ignored is distracting.

My thoughts, at least.