Ran into this issue while testing out another unrelated issue. I went to check out tag pyqtgraph-0.11.0 and did python.setup.py install and got the following error:

$ python setup.py install
Traceback (most recent call last):
  File "setup.py", line 70, in <module>
    version, forcedVersion, gitVersion, initVersion = helpers.getVersionStrings(pkg='pyqtgraph')
  File "tools/setupHelpers.py", line 470, in getVersionStrings
    _, local = gitVersion.split('+')
ValueError: need more than 1 value to unpack

The issue here is that gitVersion is reporting the version 0.11.0 with no +. We can work around this by using str.partition("+") instead which won't blow up should a + not be present.