Concatenate or print list elements with a trailing comma in Python

Question

I am having a list as : ``` >>> l = ['1', '2', '3', '4'] ``` if I use join statement, ``` >>> s = ', '.join(l) ``` will give me output as : ``` '1, 2, 3, 4' ``` But, what I have to do If I want output as : ``` '1, 2, 3, 4,' ``` (I know that I can use string concat but I want to know some better way) .

Accepted Answer

String concatenation is the best way:

```
l = ['1', '2', '3', '4']  # original list
s = ', '.join(l) + ','
```

but you have other options also:

Mapping to comma-ended strings, then joining:

```
l = ['1', '2', '3', '4']  # original list
s = ' '.join(map(lambda x: '%s,' % x, l))
```

Appending empty string to the joined list (don't modify original `l` list!):

```
l = ['1', '2', '3', '4']  # original list
s = ', '.join(l + ['']).rstrip(' ')
```

Using string formatting in place of concatenation:

```
l = ['1', '2', '3', '4']  # original list
s = '%s,' % (', '.join(l))
```

Concatenate or print list elements with a trailing comma in Python

Solution

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