Very basic Python question (strings, formats and escapes)

Question

I am starting to learn Python with an online guide, and I just did an exercise that required me to write this script:

from sys import argv

script, filename = ar         


        

Answer 1

The guide is suggesting creating a single string and writing it out rather than callingwrite() six time which seems like good advice.

You've got three options.

You could concatentate the strings together like this:

line1 + "\n" + line2 + "\n" + line3 + "\n"

or like this:

"\n".join(line1,line2,line3) + "\n"

You could use old string formatting to do it:

"%s\n%s\n%s\n" % (line1,line2,line3)

Finally, you could use the newer string formatting used in Python 3 and also available from Python 2.6:

"{0}\n{1}\n{2}\n".format(line1,line2,line3)

I'd recommend using the last method because it's the most powerful when you get the hang of it, which will give you:

target.write("{0}\n{1}\n{2}\n".format(line1,line2,line3))