Preferred Python idiom for handling non-existing dictionary keys and why?

[Quentin Crain]

Hello again All!

(First, I would like to mention I did try to google
for the answer here!)

Say I am populating a dictionary with a list and
appending. I have written it thusly:

  d={}
  for (k,v) in somedata():
      try:
          d[k].append(v)
      except KeyError:
          d[k]=[v]

I could have written:

  d={}
  for (k,v) in somedata():
      if (k in d):
          d[k].append(v)
      else:
          d[k]=[v]


Which is perferred and why? Which is "faster"?

Thanks!!

  Quentin


=====
-- Quentin Crain

------------------------------------------------
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