lib/oe: Fix collections ABCs DeprecationWarning in Python 3.7+
- Prefer collections.abc (new in Python 3.3) over collections for abstract base classes
- In Python 3.8, the abstract base classes in collections.abc will no longer be exposed in
the regular collections module. This will help create a clearer distinction between
the concrete classes and the abstract base classes."
- https://docs.python.org/3.7/whatsnew/3.7.html#deprecated
- see https://github.com/python/cpython/commit/
c66f9f8d3909f588c251957d499599a1680e2320
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
