loongson/pypi: links for singledispatch

loongson/pypi singledispatch-3.7.0-py2.py3-none-any.whl
loongson/pypi singledispatch-3.4.0.3-py3-none-any.whl
loongson/pypi singledispatch-3.4.0.3-py2-none-any.whl