python for loop start, end code example

Example 1: python for loop start, end

my_list = [1, 2, 3]
my_list.reverse()           # my_list is modified
print(my_list)              # '[3, 2, 1]'
my_revert = my_list[::-1]   # my_list stays [3, 2, 1]
print(my_revert)            # '[1, 2, 3]'
# Item by item reverse with range(<start>, <end>, <step>)
for i in range(len(my_list), 0, -1):		# my_list is [3, 2, 1]
    print(my_list[i-1])		# '1' '2' '3'
for i in reversed(range(len(my_list))):
    print(my_list[i])       # '1' '2' '3'

Example 2: python loop back to start

def main(): #defines the area in indents that will be triggered with main()#
  print('hi')
  yn = input('Wanna loop back to the start? ')
  if yn = 'yes':
    main() #loops back to where we defined main#
    
main() #This starts the main loop, without this, main would just be defined but not run#

Example 3: hwo to end a for loop [ython

for x in range (0, 20 + 1, 5):
    print(x)
    if x == 20: break

print('bob')

"""
output:

0
5
10
15
20
bob

"""

#I hope it helps! -Andrew Ma

#make sure when you print bob don't indent or else
it will think it is part of the for loop! :)