In [4]: base = "file:///tmp/tmp60uy_xo4tng_pi/devices/10.47.12.11/schema/current/AXLAPI.wsdl"

In [5]: location = "AXLSoap.xsd"

In [6]: absolute_location(location, base)
Out[6]: '/home/oheddela/file:/tmp/tmp60uy_xo4tng_pi/devices/10.47.12.11/schema/current/AXLSoap.xsd'

In [7]: from six.moves.urllib.parse import urljoin

In [8]: urljoin(base, location)
Out[8]: 'file:///tmp/tmp60uy_xo4tng_pi/devices/10.47.12.11/schema/current/AXLSoap.xsd'

In [9]: import os

In [10]: os.path.isabs(location)
Out[10]: False

In [11]: os.path.realpath(location)
Out[11]: '/home/oheddela/AXLSoap.xsd'

In [12]: os.path.dirname(base)
Out[12]: 'file:///tmp/tmp60uy_xo4tng_pi/devices/10.47.12.11/schema/current'

In [13]: os.path.join(os.path.dirname(base), location)
Out[13]: 'file:///tmp/tmp60uy_xo4tng_pi/devices/10.47.12.11/schema/current/AXLSoap.xsd'

In [14]: os.path.realpath(os.path.join(os.path.dirname(base), location))
Out[14]: '/home/oheddela/file:/tmp/tmp60uy_xo4tng_pi/devices/10.47.12.11/schema/current/AXLSoap.xsd'