jupyter notebokk報錯情況出現背景：手動下載pytoch的whl安裝文件，使用pip install pytorch.whl命令安裝pytorch。
出現的原因是因為有兩個重復的文件libiomp5md.dll在python環境中。
解決辦法：
第一種：搜索anaconda安裝文件夾，把另外一個不在torch庫下的文件備份刪除。
第二種：在代碼中添加下面兩行代碼
import os
os.environ["KMP_DUPLICATE_LIB_OK"]="TRUE"
錯誤官方提示：
OMP: Hint This means that multiple copies of the OpenMP runtime have been linked into the program. That is dangerous, since it can degrade performance or cause incorrect results. The best thing to do is to ensure that only a single OpenMP runtime is linked into the process, e.g. by avoiding static linking of the OpenMP runtime in any library. As an unsafe, unsupported, undocumented workaround you can set the environment variable KMP_DUPLICATE_LIB_OK=TRUE to allow the program to continue to execute, but that may cause crashes or silently produce incorrect results. For more information, please see http://www.intel.com/software/products/support/.