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How to convert a string with comma-delimited items to a list in Python?

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How do you convert a list of objects to a list of strings in Python?

To convert a list to a string, use Python List Comprehension and the join() function. The list comprehension will traverse the elements one by one, and the join() method will concatenate the list's elements into a new string and return it as output.

How do you print a list of elements separated by a comma in Python?

We use another way to demonstrate the working of a Python list to a comma-separated string. At first, we initialize a list and use the print function to print original values in the list. Then we use a loop to add a comma at the end of each value, after altering each value to a string.


Like this:

>>> text = 'a,b,c'
>>> text = text.split(',')
>>> text
[ 'a', 'b', 'c' ]

Just to add on to the existing answers: hopefully, you'll encounter something more like this in the future:

>>> word = 'abc'
>>> L = list(word)
>>> L
['a', 'b', 'c']
>>> ''.join(L)
'abc'

But what you're dealing with right now, go with @Cameron's answer.

>>> word = 'a,b,c'
>>> L = word.split(',')
>>> L
['a', 'b', 'c']
>>> ','.join(L)
'a,b,c'

The following Python code will turn your string into a list of strings:

import ast
teststr = "['aaa','bbb','ccc']"
testarray = ast.literal_eval(teststr)

I don't think you need to

In python you seldom need to convert a string to a list, because strings and lists are very similar

Changing the type

If you really have a string which should be a character array, do this:

In [1]: x = "foobar"
In [2]: list(x)
Out[2]: ['f', 'o', 'o', 'b', 'a', 'r']

Not changing the type

Note that Strings are very much like lists in python

Strings have accessors, like lists

In [3]: x[0]
Out[3]: 'f'

Strings are iterable, like lists

In [4]: for i in range(len(x)):
...:     print x[i]
...:     
f
o
o
b
a
r

TLDR

Strings are lists. Almost.


In case you want to split by spaces, you can just use .split():

a = 'mary had a little lamb'
z = a.split()
print z

Output:

['mary', 'had', 'a', 'little', 'lamb'] 

If you actually want arrays:

>>> from array import array
>>> text = "a,b,c"
>>> text = text.replace(',', '')
>>> myarray = array('c', text)
>>> myarray
array('c', 'abc')
>>> myarray[0]
'a'
>>> myarray[1]
'b'

If you do not need arrays, and only want to look by index at your characters, remember a string is an iterable, just like a list except the fact that it is immutable:

>>> text = "a,b,c"
>>> text = text.replace(',', '')
>>> text[0]
'a'