Replace deprecated imp module with importlib

[hugovk]

This library uses the imp module which has been deprecated since Python 3.4 and set for removal in 3.12:

• Raised PendingDeprecationWarning since 3.4 (2014)
• Raised DeprecationWarning since 3.5 (2015)
• Updated DeprecationWarning to say removal in 3.12 since 3.10 (2021)
• Removal planned for 3.12 (2023)

Python 3.12 is set for release on 2023-10-02 and this library is one of the top 5,000 most-downloaded from PyPI.

Please could you upgrade to use importlib? The imp docs have suggestions on what to use to replace each function and constant.

[dsagal]

Actually, asttokens does not use the imp module. It is present in one of test fixtures that tests read for testing some parsing logic. Anything in the tests/testdata directory is only parsed by tests but not executed, and it shouldn't make a difference whether an import mentioned in that directory is deprecated or if it's even exists.

[hugovk]

Good to hear, thanks for checking!