Writing a list to a file with Python

Is this the cleanest way to write a list to a file, since writelines() doesn't insert newline characters?

file.writelines(["%sn" % item  for item in list])

It seems like there would be a standard way...

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EDIT Adding info from Thomas' comment

Don't forget to open the file first

thefile = open('test.txt', 'w')

I'd use a loop:

for item in thelist:
  thefile.write("%sn" % item)

or:

for item in thelist:
  print>>thefile, item

If you're keen on a single function call, at least remove the square brackets [] so that the strings to be printed get made one at a time (a genexp rather than a listcomp) -- no reason to take up all the memory required to materialize the whole list of strings.

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What are you going to do with the file? Does this file exist for humans, or other programs with clear interoperability requirements, or are you just trying to serialize a list to disk for later use by the same python app. If the second case is it, you should be pickleing the list.

import pickle

with open('outfile', 'wb') as fp:
    pickle.dump(itemlist, fp)

To read it back:

with open ('outfile', 'rb') as fp:
    itemlist = pickle.load(fp)

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最好的方法是：

outfile.write("n".join(itemlist))

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