python之第 1 行的 SyntaxError : Non-UTF-8 code starting with '\x90' in file C:\Python36\python. exe，但未声明编码

SyntaxError: Non-UTF-8 code starting with '\x90' in file 
C:\Python36\python.exe on line 1, but no encoding declared 

我不明白为什么它会在我想打开解释器时向我显示。有人可以帮帮我吗？