Five years ago, in https://github.com/matplotlib/matplotlib/commit/e91c5a1c91c54b1b23c1b469ba72c5553ae3d1ce, I commented out the line that was making boilerplate look first in the local tree, without removing the comment that went with that line.  I don't know why I did that.  If the present behavior is what we want, then the first two lines in the excerpt from boilerplate, below, should be deleted.  I suspect the present behavior makes sense because otherwise python code would be found in the source tree but compiled extensions would be from the installed version, so they could be out of sync.
```python
# import the local copy of matplotlib, not the installed one
#sys.path.insert(0, './lib')
from matplotlib.axes import Axes
```