loongson/pypi: links for popen

loongson/mirror popen-0.1.20.tar.gz
loongson/mirror popen-0.1.19.tar.gz
loongson/mirror popen-0.1.18.tar.gz
loongson/mirror popen-0.1.17.tar.gz
loongson/mirror popen-0.1.15.tar.gz
loongson/mirror popen-0.1.14.tar.gz
loongson/mirror popen-0.1.13.tar.gz
loongson/mirror popen-0.1.12.tar.gz