* remove functions not belong to public-api from __all__

* fix code style

* fix error in distributed

* fix tess split fold

* format

* add audio feature dataset

* fix coding style

* fix coding style2

* rm librosa

* rm voxceleb

* rm librosa in test

* add scipy fftpack

* add functional

* fix setup

* fix setup2

* rm colorlog

* refactor dataset __init__.py

* fix converage

* fix librosa import error

* fix windows test

* fix windows ci

* rm datasets

* fix setup

* remove testdata

* add librosa in requirement

* add librosa in requirement2

* change librosa to 0.8.1

* update ci docker

* fix ci error

* fix ci error2

* fix ci coverage

* fix converage

* fix coverage

* rm audio_base in test, notest,test=coverage

* fix copyright

* rm backend

* add datast in __init__

* rm compliance&&add function test

* fix setup

* fix windows

* fix windows2

* fix test timeout

* add backend & datasets

* fix bugs

* fix ci time issue

* add dataset test

* rm test_audio_feature

* avoid windows isssue, tmp

* note windows isssue

* skip windows issue

* refactor dataset test

* add dataset.py

* fix dtype in layers.mfcc

* fix ci-static-check

* fix dtype in layers.mfcc && fix ci-static-check

* add relative accuracy

* modity API.spec

* skip cuda11.2 test

* skip cuda11.2 test2

* skip cuda11.2

* change dataset name

* fix format

* update api.spec

* update api.spec2

* fix coverage

* add dataset test

* rm download load dict

* rm download load dict in init

* update api.spec3

* fix dataset coverage

* fix coverage

* fix coverage2

* restore api.spec

* restore api.spec2

* fix api-spec 3

* fix api-spec 4

* fix api.spec

* fix api.spec6

* refactor init_backend

* fix typo

* change paddleaudio backend set

* fix get_current_audio_backend()

* fix format

* fix format2

* remove format in parameters

* fix format2

* add warning massage in wave_backend && remove redundant audio util

* rm audio util in print_signatures

* fix format3

* add tess dataset license

* format warning

* add more info in warning msg

* add paddleaudio version check

* replace dataset esc50 with tess

* add tess dataset && rm numpy transform in dataset.py

* fix set audio backend bug

* fix equal error

* fix format && coverage error

* add api example

* fix format

* fix error

* fix typo

* add noqa in __init__

* fix backend doc example error

* rm seed in dataset

* update bakcend example

* fix typo

* fix typo

* fix example err

* fix typo

* fix ci dataset test

* fix example fil

* try to fix ci

* clean dataset doc

* change get_current_audio_backend to get_current_backend

* creplace paddle.audio.backends.info with paddle.audio.info, same with load, save

* fix ci error

* repalce api in test_audio_backend

* fix save&&set_backend exmaple