loongson/pypi: links for flat-tree

loongson/mirror flat-tree-0.0.1a8.tar.gz
loongson/mirror flat_tree-0.0.1a8-py3-none-any.whl
loongson/mirror flat-tree-0.0.1a6.tar.gz
loongson/mirror flat_tree-0.0.1a6-py3-none-any.whl
loongson/mirror flat-tree-0.0.1a5.tar.gz
loongson/mirror flat-tree-0.0.1a4.tar.gz
loongson/mirror flat-tree-0.0.1a3.tar.gz
loongson/mirror flat-tree-0.0.1a2.tar.gz