在Windows上通过conda shell安装时，我遇到keras和keras-gpu的依赖冲突。
之前的冲突发生在nltk和keras之间，我卸载了nltk个包。但即使是现在存在以下冲突：
(base) C:\WINDOWS\system32> conda install keras
Solving environment: failed
UnsatisfiableError: The following specifications were found to be in conflict:
- backports.functools_lru_cache
- keras
Use "conda info <package>" to see the dependencies for each package.
如何解决此错误并成功安装keras和keras-gpu？