COMPAT: 32bit compat on indexing for MI.remove_unused_levels
# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/15948?src=pr&el=h1) Report
> Merging [#15948](https://codecov.io/gh/pandas-dev/pandas/pull/15948?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/751119f3bf9da9ce4291ebe7d67d5ebacb16159d?src=pr&el=desc) will **decrease** coverage by `<.01%`.
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/15948/graphs/tree.svg?token=eZ4WkYLtcO&src=pr&height=150&width=650)](https://codecov.io/gh/pandas-dev/pandas/pull/15948?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #15948      +/-   ##
==========================================
- Coverage   90.99%   90.99%   -0.01%     
==========================================
  Files         145      145              
  Lines       49569    49570       +1     
==========================================
  Hits        45106    45106              
- Misses       4463     4464       +1
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `88.76% <100%> (-0.01%)` | :arrow_down: |
| #single | `40.56% <0%> (-0.01%)` | :arrow_down: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/15948?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/indexes/multi.py](https://codecov.io/gh/pandas-dev/pandas/pull/15948?src=pr&el=tree#diff-cGFuZGFzL2luZGV4ZXMvbXVsdGkucHk=) | `96.7% <100%> (ø)` | :arrow_up: |
| [pandas/core/common.py](https://codecov.io/gh/pandas-dev/pandas/pull/15948?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvY29tbW9uLnB5) | `90.68% <0%> (-0.35%)` | :arrow_down: |

------

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> **Legend** - [Click here to learn more](https://docs.codecov.io/docs/codecov-delta)
> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/15948?src=pr&el=footer). Last update [751119f...34049ef](https://codecov.io/gh/pandas-dev/pandas/pull/15948?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).