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From: Erik <python@lucidity.plus.com>
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Subject: Re: repeat items in a list
Date: Sat, 26 Mar 2016 23:23:53 +0000
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Hi,

On 26/03/16 22:12, beliavsky--- via Python-list wrote:
> I can create a list that has repeated elements of another list as follows:
>
> xx = ["a","b"]
> nrep = 3
> print xx
> yy = []
> for aa in xx:
>      for i in range(nrep):
>          yy.append(aa)
> print yy
>
> output:
> ['a', 'b']
> ['a', 'a', 'a', 'b', 'b', 'b']
>
> Is there a one-liner to create a list with repeated elements?

yy = reduce(lambda a, b: a + b, ([i] * nrep for i in xx), [])

Or, if you want to "import operator" first, you can use 'operator.add' 
instead of the lambda (but you _did_ ask for a one-liner ;)).

Out of interest, why the fascination with one-liners?

E.