CLN remove 'import pandas as pd' from pandas/core/generic.py
- [x] Ensure all linting tests pass, see [here](https://pandas.pydata.org/pandas-docs/dev/development/contributing.html#code-standards) for how to run them

---

will do the rest (excluding `pandas/tests`) and add a check if this is the kind of thing we want
nice thanks @MarcoGorelli 