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To: John Gordon <gordon@panix.com>
Subject: Re: Referrer key missing form os.environ dictionary?
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Xref: csiph.com comp.lang.python:54743

On 9/25/13 10:26 AM, John Gordon wrote:
> You could try this:
>
>      try:
>          referer = os.environ.get('HTTP_REFERER', 'UnknownRef')
>      except KeyError:
>          referer = None
>
>      if not referer:
>          referer = 'UnknownRef'
There's no need for the "except KeyError" clause.  dict.get never raises 
KeyError, this code will assign 'UnknownRef' in the case the environment 
variable is missing.

--Ned.