How to convert a tuple to a string in Python?

Question

After the MySQL select statement, I leave the following:

set([(' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',)]) 

I would like to have

 emaillist = "\n".join(queryresult) 

at the end, enter the line:

 [e-mail] [e-mail] [e-mail] etc 

What would be the proper way to convert this nested tuple to a string?

Answer 1

So far, you are sure that you have only one element per tuple:

 '\n'.join(elem[0] for elem in queryresult) 

Answer 2

Try it and see

 >>> something=set([(' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',), (' [e-mail] ',)]) >>> print '\n'.join(''.join(s) for s in something) [e-mail] [e-mail] [e-mail] [e-mail] [e-mail] [e-mail] [e-mail] [e-mail] 

Note. A join can only work with strings, but tuple elements are set elements. To make the connection work, you need to iterate over the set to convert each element to a string. Finally, once you are done, you can join them as your heart desires.

On a side note. The round way :-)

 >>> print "\n".join(re.findall("\'(.*?)\'",pprint.pformat(something))) [e-mail] [e-mail] [e-mail] [e-mail] [e-mail] [e-mail] [e-mail] [e-mail] 

Answer 3

Understanding Lists in Strings

 [item[0] for item in queryresult] 

should help. eg,

 emaillist = "\n".join([item[0] for item in queryresult]) 

.. it makes strong assumptions about the type and structure of queryresult, however.

---

change

Generator expression is even better:

 emaillist = "\n".join(item[0] for item in queryresult) 

thanks @delnan for this update

Answer 4

 new = '\n'.join(x[0] for x in old)