remove reference to splitport()

[ccurvey]

with python 3.8 I'm getting warnings that splitport() is deprecated. I rolled by own, rather than trying to use the official urlparse() method as the official version does not handle "host:port" style URLs.

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This change is 

[andersk]

To use the official urlparse function, you just need to prepend a //:

>>> from urllib.parse import urlparse
>>> u = urlparse("//" + "localhost:1234")
>>> u.hostname
'localhost'
>>> u.port
1234

Additionally, urlparse supports IPv6 where this hand-rolled parser does not:

>>> u = urlparse("//" + "[::1]:1234")
>>> u.hostname
'::1'
>>> u.port
1234

Or you can use SplitResult to avoid string concatenation:

>>> from urllib.parse import SplitResult
u = SplitResult("", "[::1]:1234", "", "", "")
>>> u.hostname
'::1'
>>> u.port
1234

[jaysonsantos]

Hey there @ccurvey what do you think of trying @andersk 's approach?

[andersk]

• Opened Avoid urllib.parse.splitport DeprecationWarning #257.