s = "Hello World"

s.append("aaa")

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-2-2ab7add94dc3> in <module>
----> 1 s.append("aaa")

AttributeError: 'str' object has no attribute 'append'

t = s + "aaa"

print(t)

Hello Worldaaa

import csv

def read_building(fname):
    with open(fname) as f:
        data = csv.reader(f,delimiter=',')
        for row in data:
            print("insert into BUILDING values ('"+row[0].strip()+"','"+row[1].strip()+"');")

def main():
    read_building("building-codes.csv")

main()

numbers = [10,20,15,40]
sum = 0
for x in numbers:
    sum = sum + x
print(sum)

85

numbers = [10,20,15,40]
product = 1
for x in numbers:
    product = product * x
print(product)

120000

def add_numbers(nums):
    sum = 0
    for x in nums:
        sum = sum + x
    return(sum)

print(add_numbers([1,2,3]))

6

print(add_numbers([10,40,90]))

140