Answer 1

Function returns none by default .

print(f'The sum of a and b is {add("all","of you")}')

Use double quotes to differentiate it from single quotes .

Answer 2

∆BH∆Y , i would not recommend to print from the function. add() function should only calculate and then return the result. this could be like:

# Defining a function add
def add(a,b):
return a + b # <<<<<<<<
#print(a+b)

# Calling the function add normally: 1st case
print(add(4,7)) # <<<<<<<<

# Calling the function add using f strings: 2nd case
print (f'The sum of a and b is {add(4,7)}')

# Calling the function add usin fstrings, now; concatenation: 3rd case
print(f'The sum of a and b is {add("all ","of you")}')

Answer 3

∆BH∆Y

"""add(4,7)

# Calling the function add using f strings: 2nd case
print (f'The sum of a and b is {add(4,7)}')
"""

In the first ,add(4, 7) you aren't printing the actual function but in second one you are doing so .

Answer 4

# input
print(print('hello world'))
# output
hello world
None
# double print function creates a None always. I guess print(print('hello world')) should produce -->
hello world
None
None ( not sure, we can try it )
So print(add(4,7)) -->
print(print(4+7)) -->
11
None