Merge pull request nipype#15 from effigies/ci/py39

CI: Test on Python 3.9

.github/workflows/pythonpackage.yml

@@ -1,6 +1,11 @@
 #This workflow will install Python dependencies, run tests and lint with a variety of Python versions
 # For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions
 
+# Note that editable installs of Pydra and the task package is useful to ensure that the
+# template describes namespace packages that can be used in various development environments.
+# Packages that use it probably do not want to continue testing with editable installations,
+# quadrupling their test load.
+
 name: Python package
 
 # Set once
@@ -18,7 +23,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.7, 3.8]
+        python-version: [3.7, 3.8, 3.9]
         pip-flags: ['', '--editable']
         pydra:
         - 'pydra'

README.md

@@ -16,6 +16,8 @@ All tasks will be inserted into the `pydra.tasks.<yourtaskpackagename>` namespac
 1. An example subpackage is found in `pydra/tasks/<yourpackagename>/utils`.
    You may wish to add tools to it or delete it.
 1. You may want to initialize a [Sphinx] docs directory.
+1. Review the workflow in `.github/workflows/pythonpackage.yml`. Testing editable installations
+   is probably not useful unless you are reconfiguring namespace packages.
 1. **Update this README after creating the new repository.**
 
 [Sphinx]: https://www.sphinx-doc.org/en/master/usage/quickstart.html