doc: typo
doc: typo

fix copy-paste from golang/mobile
fix #1
lifei/gopy,kellrott/gopy,go-python/gopy-gen,go-python/gopy,ericsnowcurrently/gopython-gopy,ericsnowcurrently/gopython-gopy,go-python/gopy,lifei/gopy,kellrott/gopy,go-python/gopy-gen