BUG: Fix Python2 long unsupport in _can_hold_element

[Licht-T]

• closes RecursionError when passing long to fillna #18316
• tests added / passed
• passes git diff upstream/master -u -- "*.py" | flake8 --diff
• whatsnew entry

[Licht-T]

Where should I add _can_hold_element tests?

[jreback]

i think #18385 also looking at this issue

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@8512cc5). Click here to learn what that means.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master   #18399   +/-   ##
=========================================
  Coverage          ?   91.34%           
=========================================
  Files             ?      164           
  Lines             ?    49730           
  Branches          ?        0           
=========================================
  Hits              ?    45426           
  Misses            ?     4304           
  Partials          ?        0

Flag	Coverage Δ
#multiple	89.14% <100%> (?)
#single	39.62% <66.66%> (?)

Impacted Files	Coverage Δ
pandas/core/internals.py	94.47% <100%> (ø)

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[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@8512cc5). Click here to learn what that means.
The diff coverage is 100%.

@@            Coverage Diff            @@
##             master   #18399   +/-   ##
=========================================
  Coverage          ?   91.34%           
=========================================
  Files             ?      164           
  Lines             ?    49730           
  Branches          ?        0           
=========================================
  Hits              ?    45426           
  Misses            ?     4304           
  Partials          ?        0

Flag	Coverage Δ
#multiple	89.14% <100%> (?)
#single	39.62% <66.66%> (?)

Impacted Files	Coverage Δ
pandas/core/internals.py	94.47% <100%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 8512cc5...703e77e. Read the comment docs.

[Licht-T]

@jreback Oops! I'll close this issue!