You can sum numbers in a list simply with the sum() built-in:
sum(your_list)
It will sum as many number items as you have. Example:
my_list = range(10, 17)
my_list
[10, 11, 12, 13, 14, 15, 16]
sum(my_list)
91
For your specific case:
For your data convert the numbers into int
first and then sum the numbers:
data = ['5', '4', '9']
sum(int(i) for i in data)
18
This will work for undefined number of elements in your list (as long as they are "numbers")
Thanks for @senderle's comment re conversion in case the data is in string format.
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