Parece que não é possível encontrar um arquivo. Por favor, verifique seu PATH
e verifique se ele aponta para a sua instalação do Python.
Esse cara teve um problema semelhante:
Well, it looks like I had this setup in my path:
C:\Users\MYUSERNAME\AppData\Local\Programs\Python\Python35-32\Scripts C:\Users\MYUSERNAME\AppData\Local\Programs\Python\Python35-32\
I don't know how that was set or what installed that, perhaps docker toolbox? Not sure, but once I changed the path to be pointed to python2.7 in my windows environment, then everything started working correctly and it pulled all the images that I needed for this.
Thanks for your prompt response.