How would you make a comma-separated string from a list of strings?

Question

What would be your preferred way to concatenate strings from a sequence such that between every two consecutive pairs a comma is added. That is, how do you map, for instance

Answer 1

Here is a alternative solution in Python 3.0 which allows non-string list items:

>>> alist = ['a', 1, (2, 'b')]

• a standard way

  >>> ", ".join(map(str, alist))
  "a, 1, (2, 'b')"
  

• the alternative solution

  >>> import io
  >>> s = io.StringIO()
  >>> print(*alist, file=s, sep=', ', end='')
  >>> s.getvalue()
  "a, 1, (2, 'b')"
  

NOTE: The space after comma is intentional.