DOC: Remove flake8 errors for basics.rst and contributing_docstring.rst
xref: #24173

need to merge master # [Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/24598?src=pr&el=h1) Report
> Merging [#24598](https://codecov.io/gh/pandas-dev/pandas/pull/24598?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/62506ca3c37b6b0d84833a8329e50c000316250e?src=pr&el=desc) will **not change** coverage.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/24598/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/24598?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master   #24598   +/-   ##
=======================================
  Coverage   92.38%   92.38%           
=======================================
  Files         166      166           
  Lines       52478    52478           
=======================================
  Hits        48483    48483           
  Misses       3995     3995
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.81% <ø> (ø)` | :arrow_up: |
| #single | `43.04% <ø> (ø)` | :arrow_up: |


------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/24598?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/24598?src=pr&el=footer). Last update [62506ca...bd591d9](https://codecov.io/gh/pandas-dev/pandas/pull/24598?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/24598?src=pr&el=h1) Report
> Merging [#24598](https://codecov.io/gh/pandas-dev/pandas/pull/24598?src=pr&el=desc) into [master](https://codecov.io/gh/pandas-dev/pandas/commit/62506ca3c37b6b0d84833a8329e50c000316250e?src=pr&el=desc) will **decrease** coverage by `<.01%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/pandas-dev/pandas/pull/24598/graphs/tree.svg?width=650&token=eZ4WkYLtcO&height=150&src=pr)](https://codecov.io/gh/pandas-dev/pandas/pull/24598?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master   #24598      +/-   ##
==========================================
- Coverage   92.38%   92.38%   -0.01%     
==========================================
  Files         166      166              
  Lines       52478    52490      +12     
==========================================
+ Hits        48483    48493      +10     
- Misses       3995     3997       +2
```

| Flag | Coverage Δ | |
|---|---|---|
| #multiple | `90.81% <ø> (ø)` | :arrow_up: |
| #single | `43.05% <ø> (ø)` | :arrow_up: |

| [Impacted Files](https://codecov.io/gh/pandas-dev/pandas/pull/24598?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [pandas/core/nanops.py](https://codecov.io/gh/pandas-dev/pandas/pull/24598/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvbmFub3BzLnB5) | `94.54% <0%> (-0.37%)` | :arrow_down: |
| [pandas/util/testing.py](https://codecov.io/gh/pandas-dev/pandas/pull/24598/diff?src=pr&el=tree#diff-cGFuZGFzL3V0aWwvdGVzdGluZy5weQ==) | `88% <0%> (-0.1%)` | :arrow_down: |
| [pandas/core/strings.py](https://codecov.io/gh/pandas-dev/pandas/pull/24598/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvc3RyaW5ncy5weQ==) | `98.58% <0%> (ø)` | :arrow_up: |
| [pandas/core/indexes/accessors.py](https://codecov.io/gh/pandas-dev/pandas/pull/24598/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy9hY2Nlc3NvcnMucHk=) | `91% <0%> (ø)` | :arrow_up: |
| [pandas/core/indexes/timedeltas.py](https://codecov.io/gh/pandas-dev/pandas/pull/24598/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW5kZXhlcy90aW1lZGVsdGFzLnB5) | `90.22% <0%> (ø)` | :arrow_up: |
| [pandas/core/arrays/timedeltas.py](https://codecov.io/gh/pandas-dev/pandas/pull/24598/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL3RpbWVkZWx0YXMucHk=) | `87.99% <0%> (ø)` | :arrow_up: |
| [pandas/core/arrays/datetimes.py](https://codecov.io/gh/pandas-dev/pandas/pull/24598/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL2RhdGV0aW1lcy5weQ==) | `98.01% <0%> (ø)` | :arrow_up: |
| [pandas/core/frame.py](https://codecov.io/gh/pandas-dev/pandas/pull/24598/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvZnJhbWUucHk=) | `96.92% <0%> (ø)` | :arrow_up: |
| [pandas/core/internals/construction.py](https://codecov.io/gh/pandas-dev/pandas/pull/24598/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvaW50ZXJuYWxzL2NvbnN0cnVjdGlvbi5weQ==) | `96.67% <0%> (ø)` | :arrow_up: |
| [pandas/core/arrays/period.py](https://codecov.io/gh/pandas-dev/pandas/pull/24598/diff?src=pr&el=tree#diff-cGFuZGFzL2NvcmUvYXJyYXlzL3BlcmlvZC5weQ==) | `98.53% <0%> (+0.01%)` | :arrow_up: |
| ... and [3 more](https://codecov.io/gh/pandas-dev/pandas/pull/24598/diff?src=pr&el=tree-more) | |

------

[Continue to review full report at Codecov](https://codecov.io/gh/pandas-dev/pandas/pull/24598?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/24598?src=pr&el=footer). Last update [62506ca...be8d253](https://codecov.io/gh/pandas-dev/pandas/pull/24598?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
 Sorry, I wasn't available the last couple of days. That's the reason I didn't create the issues for `basics` and `contributing_docstring`, because they are not so simple. Can you just leave the easy changes (all the ones without the `noqa` (adding `np`...) here? I'll take care of the remaining myself in a separate PR later.  thanks @saurav2608  @saurav2608  / @jreback , I still see `flake8-rst` issues with `contributing_docstring.rst`. Is it good idea to add `# noqa` for below issues ?

```
contributing_docstring.rst:52:9: F821 undefined name 'add'
contributing_docstring.rst:54:9: F821 undefined name 'add'
contributing_docstring.rst:56:9: F821 undefined name 'add'
contributing_docstring.rst:456:16: F821 undefined name 'random'
contributing_docstring.rst:476:18: F821 undefined name 'random'
contributing_docstring.rst:477:27: F821 undefined name 'random'
contributing_docstring.rst:477:41: F821 undefined name 'string'
contributing_docstring.rst:498:19: F821 undefined name 'random'
contributing_docstring.rst:650:21: F821 undefined name 'pd'
contributing_docstring.rst:774:60: F821 undefined name 'numpy'
contributing_docstring.rst:832:31: F821 undefined name 'numpy'
contributing_docstring.rst:950:9: F821 undefined name 'Substitution'
contributing_docstring.rst:951:9: F821 undefined name 'Appender'
contributing_docstring.rst:956:9: F821 undefined name 'Substitution'
contributing_docstring.rst:957:9: F821 undefined name 'Appender'
contributing_docstring.rst:986:5: F821 undefined name 'Appender'
contributing_docstring.rst:986:14: F821 undefined name 'template'
contributing_docstring.rst:986:25: F821 undefined name '_shared_doc_kwargs'
``` Thanks for offering @iamshreeram, but we may be moving that page our of the docs into the website, so not worth fixing those at this point. You can easily find things to fix in the docstrings, those will be much more useful. `./scripts/validate_docstrings.py` should give you lots of errors to fix. :) We're hunting errors to fix, and I'm just getting started, so we appreciate your pointers, @datapythonista ! > ./scripts/validate_docstrings.py
@datapythonista , I'm seeing a lot to sift through to find something I can fix. What advice do you have to point me in the right direction? are you in the Walmart hackathon? how people is communicating there, do you have any IM? Do you think I can get an invitation? Please try - http://bit.ly/pandashackslack @datapythonista , are you able to join?