python string, best way to concat

[MRAB]

On 2014-08-27 23:59, Peter Otten wrote:
> Tim Chase wrote:
>
>> On 2014-08-27 23:42, MRAB wrote:
>>> How many parameters are there? len(self.param)
>>>
>>> Make that many placeholders and then join them together with
>>> commas:
>>>
>>> ', '.join(['?'] * len(self.param))
>>
>> I prefer the clarity of Peter Otten's suggestion of
>>
>> ', '.join('?' * len(self.param))
>>
>> over the mild obscurity of putting it in a list before
>> multiplying.
>
> As long as the OP doesn't try to transfer this to other paramstyles:
>
 >>>> ", ".join(["%s"]*3)
 > '%s, %s, %s'
 >>>> ", ".join("%s"*3) # OOPS
 > '%, s, %, s, %, s'
 >
I chose the list form for just this reason, because the OP said he was
"very new to Python".