There are several different errors in the process of installing prophet. Record them
1) Error: ModuleNotFoundError: No module named ‘pystan’
Please install pystan before installing prophet
2) Error: command ‘x86_64-apple-darwin13.4.0-clang’ failed with exit status 254
To execute the following two sentences on the command line
export CC=gcc
export CXX=g++3) Error: command ‘x86_64-apple-darwin13.4.0-clang’ failed with exit status 1
export CXX=clang