Removed debugging code
I randomly came across this code when messing around with some Mypy configurations. It looks like this code depends on third party packages which we don't even use in the code base. They also haven't been touched in 7-8 years so I assume this is dead code.

# [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=h1) Report
> Merging [#25647](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/f88613929d6c83952cb5a6bf70678a78be480baa?src=pr&el=desc) will **increase** coverage by `0.02%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/25647/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #25647      +/-   ##
==========================================
+ Coverage   91.26%   91.29%   +0.02%     
==========================================
  Files         173      173              
  Lines       52968    52948      -20     
==========================================
- Hits        48340    48337       -3     
+ Misses       4628     4611      -17
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.86% <ø> (+0.02%)` | :arrow_up: |
| #single | `41.72% <ø> (+0.01%)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/util/testing.py](https://codecov.io/gh/pandas-dev/pandas/pull/25647/diff?src=pr&el=tree#diff-cGFuZGFzL3V0aWwvdGVzdGluZy5weQ==) | `89.08% <ø> (+1.41%)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=continue).
> **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/25647?src=pr&el=footer). Last update [f886139...ec25028](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=h1) Report
> Merging [#25647](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/f88613929d6c83952cb5a6bf70678a78be480baa?src=pr&el=desc) will **increase** coverage by `0.02%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/25647/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #25647      +/-   ##
==========================================
+ Coverage   91.26%   91.29%   +0.02%     
==========================================
  Files         173      173              
  Lines       52968    52948      -20     
==========================================
- Hits        48340    48337       -3     
+ Misses       4628     4611      -17
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `89.86% <ø> (+0.02%)` | :arrow_up: |
| #single | `41.72% <ø> (+0.01%)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/util/testing.py](https://codecov.io/gh/pandas-dev/pandas/pull/25647/diff?src=pr&el=tree#diff-cGFuZGFzL3V0aWwvdGVzdGluZy5weQ==) | `89.08% <ø> (+1.41%)` | :arrow_up: |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=continue).
> **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/25647?src=pr&el=footer). Last update [f886139...ec25028](https://codecov.io/gh/pandas-dev/pandas/pull/25647?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 Thanks!