How can I convert each item in the list to string, for the purpose of joining them?

Calling str(...) is the Pythonic way to convert something to a string.

You might want to consider why you want a list of strings. You could instead keep it as a list of integers and only convert the integers to strings when you need to display them. For example, if you have a list of integers then you can convert them one by one in a for-loop and join them with ,:

print(','.join(str(x) for x in list_of_ints))

There's nothing wrong with passing integers to str. One reason you might not do this is that myList is really supposed to be a list of integers e.g. it would be reasonable to sum the values in the list. In that case, do not pass your ints to str before appending them to myList. If you end up not converting to strings before appending, you can construct one big string by doing something like

', '.join(map(str, myList))

The map function in python can be used. It takes two arguments. The first argument is the function which has to be used for each element of the list. The second argument is the iterable.

a = [1, 2, 3]   
map(str, a)  
['1', '2', '3']

After converting the list into a string you can use the simple join function to combine the list into a single string

a = map(str, a)    
''.join(a)      
'123'

a=[1,2,3]
b=[str(x) for x in a]
print b

above method is the easiest and most general way to convert list into string. another short method is-

a=[1,2,3]
b=map(str,a)
print b