CLN: Remove unicode u string prefix

[jschendel]

• xref CLN: remove PY2 #25725
• tests added / passed
• passes git diff upstream/master -u -- "*.py" | flake8 --diff

More Python 2 removal. Could use a second pair of eyes to make sure the regex I used to make these fixes wasn't overzealous anywhere.

[jschendel]

I think as-is this will fail CI only because the following xfailed test is now passing, and we're being strict with XPASS here:

pandas/pandas/tests/io/formats/test_to_csv.py

Lines 355 to 368 in dca809b

	@pytest.mark.xfail
	def test_to_csv_string_array_utf8(self):
	# GH 10813
	str_array = [{'names': ['foo', 'bar']}, {'names': ['baz', 'qux']}]
	df = pd.DataFrame(str_array)
	expected_utf8 = '''\
	,names
	0,"[u'foo', u'bar']"
	1,"[u'baz', u'qux']"
	'''
	with tm.ensure_clean('unicode_test.csv') as path:
	df.to_csv(path, encoding='utf-8')
	with open(path, 'r') as f:
	assert f.read() == expected_utf8

The only change I made a was removing the u prefix on lines 362-3, so it looks like this was only failing on Python 3 due to the expected string containing the prefixes? I was able to manually confirm that this appears to be working on Python 3 and failing on Python 2 in the 0.24.2 release, meaning the issue was Python 2 specific and we can remove the xfail?

cc @jreback : Does the above make sense to you, or am I misinterpreting the issue? If so, does it make sense to also close the associated issue #10813?

[codecov]

Codecov Report

Merging #25864 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #25864   +/-   ##
=======================================
  Coverage   91.47%   91.47%           
=======================================
  Files         173      173           
  Lines       52868    52868           
=======================================
  Hits        48362    48362           
  Misses       4506     4506

Flag	Coverage Δ
#multiple	90.04% <0%> (ø)	⬆️
#single	41.82% <0%> (ø)	⬆️

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[codecov]

Codecov Report

Merging #25864 into master will increase coverage by <.01%.
The diff coverage is 91.62%.

@@            Coverage Diff             @@
##           master   #25864      +/-   ##
==========================================
+ Coverage   91.47%   91.47%   +<.01%     
==========================================
  Files         173      173              
  Lines       52868    52872       +4     
==========================================
+ Hits        48362    48366       +4     
  Misses       4506     4506

Flag	Coverage Δ
#multiple	90.04% <87.43%> (ø)	⬆️
#single	41.82% <37.69%> (-0.01%)	⬇️

Impacted Files	Coverage Δ
pandas/core/arrays/categorical.py	95.96% <ø> (ø)	⬆️
pandas/core/indexing.py	90.87% <ø> (ø)	⬆️
pandas/core/arrays/base.py	98.27% <ø> (ø)	⬆️
pandas/core/indexes/multi.py	95.62% <ø> (ø)	⬆️
pandas/core/dtypes/dtypes.py	96.1% <ø> (ø)	⬆️
pandas/errors/__init__.py	100% <ø> (ø)	⬆️
pandas/core/reshape/pivot.py	96.55% <100%> (ø)	⬆️
pandas/io/formats/format.py	97.99% <100%> (ø)	⬆️
pandas/core/arrays/period.py	98.53% <100%> (ø)	⬆️
pandas/core/indexes/period.py	92.06% <100%> (ø)	⬆️
... and 8 more

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[jreback]

that issue looks pretty confusing so not sure
you can make strict=False to get this PR passing

[jschendel]

okay, marked it as @pytest.mark.xfail(strict=False)

[jreback]

thanks @jschendel