Updating tensorflow_datasets/audio to remove pylint errors

[ManishAradwad]

Related with Issue #1644

I'm remaining with following errors:

groove.py:162:0: E0012: Bad option value 'g-complex-comprehension' (bad-option-value)
groove.py:31:0: E0401: Unable to import 'tensorflow.compat.v2' (import-error)
groove.py:82:8: C0103: Variable name "v2" doesn't conform to snake_case naming style (invalid-name)
groove.py:61:0: R0903: Too few public methods (0/2) (too-few-public-methods)
groove.py:156:70: C0103: Variable name "f" doesn't conform to snake_case naming style (invalid-name)
groove.py:167:4: R0914: Too many local variables (24/15) (too-many-locals)
groove.py:207:16: C0103: Variable name "pm" doesn't conform to snake_case naming style (invalid-name)
groove.py:91:0: R0903: Too few public methods (0/2) (too-few-public-methods)

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Your code has been rated at 8.24/10 (previous run: 8.24/10, +0.00)

Can somebody plz help me correct these?

[ChanchalKumarMaji]

For eg., running the code below gives -

(tfds_env) chanchal@chanchal:~/datasets$ ./oss_scripts/lint.sh tensorflow_datasets/audio/
--2020-03-15 10:22:55--  https://raw.githubusercontent.com/tensorflow/tensorflow/master/tensorflow/tools/ci_build/pylintrc
Resolving raw.githubusercontent.com (raw.githubusercontent.com)... 199.232.20.133
Connecting to raw.githubusercontent.com (raw.githubusercontent.com)|199.232.20.133|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 11007 (11K) [text/plain]
Saving to: ‘/tmp/pylintrc’

/tmp/pylintrc                             100%[===================================================================================>]  10.75K  --.-KB/s    in 0.001s  

2020-03-15 10:22:56 (12.8 MB/s) - ‘/tmp/pylintrc’ saved [11007/11007]

Using config file /tmp/pylintrc
************* Module tensorflow_datasets.audio.libritts_test
C: 27, 0: Missing class docstring (missing-docstring)
************* Module tensorflow_datasets.audio.nsynth_test
W: 25, 2: Access to a protected member _SPLIT_SHARDS of a client class (protected-access)
************* Module tensorflow_datasets.audio.nsynth
C:144, 2: Missing method docstring (missing-docstring)
************* Module tensorflow_datasets.audio.librispeech_test
C: 27, 0: Missing class docstring (missing-docstring)
************* Module tensorflow_datasets.audio.libritts
C: 94, 2: Missing method docstring (missing-docstring)
************* Module tensorflow_datasets.audio.groove
C:119, 2: Missing method docstring (missing-docstring)
C:166, 2: Missing method docstring (missing-docstring)
************* Module tensorflow_datasets.audio.librispeech
C:163, 2: Missing method docstring (missing-docstring)
C:175, 2: Missing method docstring (missing-docstring)
************* Module tensorflow_datasets.audio.speech_commands
C:164, 0: Line too long (81/80) (line-too-long)
C:167, 2: Missing method docstring (missing-docstring)

-----------------------------------
Your code has been rated at 9.82/10

[ManishAradwad]

@ChanchalKumarMaji @Conchylicultor Can you plz review this PR?
I'm getting following output:
Your code has been rated at 10.00/10 (previous run: 9.95/10, +0.05)