DEPR: 3.4 deprecations

[jreback]

• file open with mode of 'rU': https://docs.python.org/3/library/fileinput.html (in test_sql.py), CLN/DEPR: Fix instances of 'U'/'rU' in open(...) #7625

closed by #7204

• to_csv writing with floating point chunksize
• plotting with floating point axes slices

closed by #7162, #7164, #7165, #7166, #7172, #7182

• assert_ to assertTrue
• assertEquals to assertEqual
• assertAlmostEquals to assertAlmostEqual

[bwignall]

Some of these boxes can be checked now, correct? Have I missed anything on the assertions?

[jreback]

yep...thanks

I have a PR for 2, and 3

If you wanted to do 1 would be great!