ImportError vs ModuleNotFoundError

[seisman]

In the current source codes, sometimes we use ImportError and sometimes ModuleNotFoundError, e.g.,

pygmt/pygmt/__init__.py

Line 130 in 5fd85dd

except ImportError:

pygmt/pygmt/figure.py

Line 11 in 5fd85dd

except ModuleNotFoundError:

ModuleNotFoundError is a subclass of ImportError (https://docs.python.org/3/library/exceptions.html#ModuleNotFoundError). As per https://www.scivision.dev/python-importerror-vs-modulenotfound/, maybe we should always use ImportError.

ref: https://stackoverflow.com/questions/62854761/python3-8-whats-the-difference-between-importerror-and-modulenotfounderror