The attached patch adds support for keyword args to find, findtext, findall, and iterfind.  iter and itertext don't seem to accept a namespace argument.  The patch includes minimal tests.

The name I used for the kwargs are the same of the Python version.  The documentation uses different names, and extra args (like "namespaces") are not even documented.

I didn't have time yet to double-check if other functions needs to be updated and to add better tests that actually check for specific namespaces.