* gnu/packages/check.scm (python2-pytest): Update to 4.6.9.
(python2-pytest-bootstrap)[propagated-inputs]: Add
PYTHON2-IMPORTLIB-METADATA-BOOTSTRAP, PYTHON2-PACKAGING-BOOTSTRAP, and
PYTHON2-WCWIDTH. Replace PYTHON2-PLUGGY with PYTHON2-PLUGGY-BOOTSTRAP.
* gnu/packages/python-compression.scm (python2-zipp-bootstrap): New public variable.
* gnu/packages/python-xyz.scm (python2-importlib-resources-bootstrap): New
public variable.
(python-importlib-metadata)[native-inputs]: Change from PYTHON-PACKAGING to
PYTHON-PACKAGING-BOOTSTRAP.
[properties]: New field.
(python2-importlib-metadata-bootstrap, python2-contextlib2-bootstrap,
python2-pluggy-bootstrap): New public variables.
(python-packaging)[arguments]: Allow overriding #:tests?.
(python2-packaging-bootstrap): New public variable.
The Python 3 variant do not need these.
* gnu/packages/python-compression.scm (python-zipp)[native-inputs]: Remove
PYTHON-CONTEXTLIB2, PYTHON-PATHLIB2, and PYTHON-UNITTEST2.
[properties]: New field.
(python2-zipp)[native-inputs]: Add PYTHON2-CONTEXTLIB2, PYTHON2-PATHLIB2, and
PYTHON2-UNITTEST2.