Append values to a set in Python

python set append
Alex Gordon picture Alex Gordon · Aug 3, 2010 · Viewed 504.2k times · Source

I have a set like this:

keep = set(generic_drugs_mapping[drug] for drug in drug_input)

How do I add values [0,1,2,3,4,5,6,7,8,9,10] into this set?

Answer

Alex Martelli picture Alex Martelli · Aug 3, 2010 
keep.update(yoursequenceofvalues)

e.g, keep.update(xrange(11)) for your specific example. Or, if you have to produce the values in a loop for some other reason,

for ...whatever...:
  onemorevalue = ...whatever...
  keep.add(onemorevalue)

But, of course, doing it in bulk with a single .update call is faster and handier, when otherwise feasible.

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