问如何通过pip安装"lru"？

EN

Traceback (most recent call last):
  File "demo/cifar10_train.py", line 1, in <module>
    from keras_audio.library.cifar10 import Cifar10AudioClassifier
  File "/Users/user/keras-audio/keras-audio/keras_audio/library/cifar10.py", line 2, in <module>
    from lru import LRU
ModuleNotFoundError: No module named 'lru'

pip install lru

Collecting lru
  Using cached lru-0.1.tar.gz (1.1 kB)
    ERROR: Command errored out with exit status 1:
     command: /Users/users/venv/bin/python -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/private/var/folders/0g/wwq2q6nn35n8vmrwhw5qfk601zlkw_/T/pip-install-tohqsyc0/lru_e04682eaa31f4d3291305bac811979b4/setup.py'"'"'; __file__='"'"'/private/var/folders/0g/wwq2q6nn35n8vmrwhw5qfk601zlkw_/T/pip-install-tohqsyc0/lru_e04682eaa31f4d3291305bac811979b4/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' egg_info --egg-base /private/var/folders/0g/wwq2q6nn35n8vmrwhw5qfk601zlkw_/T/pip-pip-egg-info-kv5i7tfq
         cwd: /private/var/folders/0g/wwq2q6nn35n8vmrwhw5qfk601zlkw_/T/pip-install-tohqsyc0/lru_e04682eaa31f4d3291305bac811979b4/
    Complete output (8 lines):
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/private/var/folders/0g/wwq2q6nn35n8vmrwhw5qfk601zlkw_/T/pip-install-tohqsyc0/lru_e04682eaa31f4d3291305bac811979b4/setup.py", line 2, in <module>
        from lru import __version__ as version
      File "/private/var/folders/0g/wwq2q6nn35n8vmrwhw5qfk601zlkw_/T/pip-install-tohqsyc0/lru_e04682eaa31f4d3291305bac811979b4/lru.py", line 18
        raise KeyError, key
                      ^
    SyntaxError: invalid syntax
    ----------------------------------------
ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.