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I am new to Python and still learning the tricks.

How can i convert the following code to a single liner, is it possible in Python? There has to be a neat way of doing this.

try: image_file = self.request.files['image_path'] except: image_file = None
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  • There isn't such a thing as a single-line-try in Python. If the exception you're guarding against is a KeyError from a dict, then you could use get Commented Feb 16, 2017 at 9:09
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    what is self.request.files - is it a dictionary ? Commented Feb 16, 2017 at 9:10
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    BTW, using a naked except is generally not a good idea (unless it's at the end of a chain of named except clauses, and even then you probably want to re-raise the exception after printing a warning or performing some other processing). Always specify the exception(s) that you want to catch. Commented Feb 16, 2017 at 9:13
  • @PM2Ring thanks for the tip Commented Feb 16, 2017 at 9:14
  • @Tarptaeya i am using Tornado request handler Commented Feb 16, 2017 at 9:17

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You have a dictionary, use the dict.get() method to return a default value for missing keys:

image_file = self.request.files.get('image_path')

Also, do not use pokemon exception handling. You really don't need to catch them all here; if a key is missing, KeyError is raised, if you must use try..except should catch just that one exception with except KeyError:.

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can you please elaborate, still in the phase of trying to wrap my head around python
I love the phrase "pokemon exception handling". :)
@Baig: I've linked to the appropriate documentation for dictionaries. You didn't tell us more about where self.request comes from, is this code from a Tornado request handler perhaps?
@MartijnPieters yes it is from Tornado request handler
@Baig: that's a standard Python dictionary, so any of the standard dictionary operations apply there.

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