what it mean by for num in range (6) code example

Example 1: for in range loop python

#there are two possibilities for a for loop
#first one is with a range()
#range() just generates lists after the following pattern

print(range(4))
>>> [0,1,2,3]
print(range(1,4))
>>> [1,2,3]
print(range(2,10,2))
>>> [2,4,6,8]

#and what the for does then is that it lets a variable (in my example x) cycle trough the list given after in

for x in range(2,10,2):
  print(x)
>>> 2
>>> 4
>>> 6
>>> 8

#so the code in the loop gets executed for every value in the given list after in
#you can also use for ... in for custom lists
#example 1:

list1 = [1,2,50,2]

for x in list1:
  print(x)

>>> 1
>>> 2
>>> 50
>>> 2

#example 2

list2 = ["bananas", "apples", "pears"]

for x in list2:
  print(x)

>>> "bananas"
>>> "apples"
>>> "pears"

Example 2: range parameters python

arr_data=[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20] 
user = int(input("Enter the product of numbers: ")) 
for i in range(0,20,1): 
    a = arr_data[i] 
    for t in range(0,20,1): 
        b = arr_data[t] 
        if (a*b) == user: 
            print(a,"x",b,"=",user) 
        else: 
            pass