Pypy37

[h-vetinari]

To unblock #34, break circular dependency with ipykernel

Closes #34

[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[h-vetinari]

Huh, it seems that ipykernel is not even a real test-dependency here. There's not even a difference in the number of skipped tests, cf. before:

+ python -m pytest --pyargs jupyter_core -k 'not test_not_on_path and not test_path_priority'
============================= test session starts ==============================
platform linux -- Python 3.8.6, pytest-6.1.2, py-1.9.0, pluggy-0.13.1
rootdir: $SRC_DIR
collected 52 items / 2 deselected / 50 selected

tests/test_application.py ........                                       [ 16%]
tests/test_command.py ..........                                         [ 36%]
tests/test_migrate.py ........                                           [ 52%]
tests/test_paths.py .....................ss.                             [100%]

================= 48 passed, 2 skipped, 2 deselected in 1.01s ==================

and after:

+ python -m pytest --pyargs jupyter_core -k 'not test_not_on_path and not test_path_priority'
============================= test session starts ==============================
platform linux -- Python 3.8.6, pytest-6.2.1, py-1.10.0, pluggy-0.13.1
rootdir: $SRC_DIR
collected 52 items / 2 deselected / 50 selected

tests/test_application.py ........                                       [ 16%]
tests/test_command.py ..........                                         [ 36%]
tests/test_migrate.py ........                                           [ 52%]
tests/test_paths.py .....................ss.                             [100%]

================= 48 passed, 2 skipped, 2 deselected in 0.78s ==================

[h-vetinari]

@conda-forge/jupyter_core This is green, PTAL

CC @mattip