# Programming Essentials Python - Basic Programming Constructs - All about for loops

Let us understand how we can loop through using `for` in Python.

• Go through range between 2 integers (5 and 10) and print them. We can use the range function to get a range between two integers.
range(5, 11)
list(range(5, 11))
list(range(5, 11, 2))
for i in range(5, 11): print(i)
• Create a list of 7 elements and print alternate numbers starting from 1.

`[1, 6, 8, 3, 7, 2, 9]`

• In this example, we are using a list. It will be covered extensively at a later point in time. `list` is one of the core Python Data Structures.
``````l = [1, 6, 8, 3, 7, 2, 9]
type(l)
cnt = 0

for i in l:

if cnt % 2 == 0: # checking if cnt is even or not

print(i)

cnt += 1 # incrementing cnt by 1
``````
• Go through the range between 2 integers (5 and 15) and print even numbers.
``````for i in range(5, 16):

if i % 2 == 0:

print(i)
``````
• Iterate through a list of months and print them.
``````months = ['January', 'February', 'March']

for month in months:

print(month)
import calendar

list(calendar.month_name)
for month in list(calendar.month_name)[1:]:

print(month)
``````

Take the list of ages and determine the category of the baby.

• Print New Born or Infant till 6 months.
• Print Toddler from 7 months to 18 months.
• Print Grown up from 19 months to 144 months.
• Print Youth from 145 months to 216 months
``````ages = [7, 3, 15, 145, 217, 18]
for age in ages:

if age <= 6:

print(f'Kid with {age} months age is "New Born or Infant"')

elif age > 6 and age <= 18:

print(f'Kid with {age} months age is "Toddler"')

elif age > 18 and age <= 144:

print(f'Kid with {age} months age is "Grown up"')

elif age > 144 and age <= 216:

print(f'Kid with {age} months age is "Youth"')

else:

print(f'Kid with {age} months age is "Adult"')
``````

Check if each number in the list of integers is even or divisible by 3.

``````ns = [1, 6, 2, 7, 9, 11, 3, 4]
for n in ns:

if n % 2 == 0 or n % 3 == 0:

print(f'Number {n} is even or divisible by 3')
``````

Check if the number in the list of integers is even and divisible by 3

``````ns = [1, 6, 2, 7, 9, 11, 3, 4]
for n in ns:

if n % 2 == 0 and n % 3 == 0:

print(f'Number {n} is even or divisible by 3')

elif n % 3 == 0:

print(f'Number {n} is divisible by 3 but not even')

elif n % 2 == 0:

print(f'Number {n} is even but not divisible by 3')
``````

Check if each salary in the list of salaries is valid. If the salary is negative or 0, then print Salary {salary_amount} is invalid. If the salary is `None`, then print Salary is Not Available.

``````sals = [100.0, 1000.0, 0.0, -100, 1200.0, None, -500]
for sal in sals:

if sal == None:

print('Salary is Not Available')

elif sal <= 0:

print(f'Salary {sal} is invalid')
``````
``````We can also use a list of tuples with an employee ID and salary. You will see examples like this as part of manipulating collections later