In version 0.3.9 of suds, the following in a WSDL file:

<xsd:import namespace="http://example.com/" schemaLocation="file:Basic.xsd" />

fails with an error that it couldn't find "/Basic.xsd"

I think the problem is the two lines in sxbasic.py that look like

    "if
 '://' not in url:"

I replaced this with 

   "if ':' not in url:"

and it worked for me, though I don't know enough about XML schemas to know if that's legit for everyone.

Thanks!
-Chris