Python – Remove square brackets from list

python

I have this list:

list1 = [['123'], ['456'], ['789']]

I want to convert this list into a string and later store it into a column in a database in this form:

123 / 456 / 789

I tried doing this:

s2 = ", ".join(repr(e) for e in list1)
print(s2)

But this is what I'm getting:

['123'], ['456'], ['789']

Any ideas on what should I do next to get the desired output?

Best Answer

You are close, but what you want to do is flatten your list of lists first, then convert to string. Like this:

" / ".join([item for sublist in list1 for item in sublist])

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The advantage of subprocess.run over os.system is that it is more flexible (you can get the stdout, stderr, the "real" status code, better error handling, etc...).

Even the documentation for os.system recommends using subprocess instead:

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