using {}.format in function for (a+b) handling

Question

I am try to write something as below:
python
def average(a,b):
return [({}+{}).format(a,b)]
avg = average(3,4)
print (avg)

it told me:
   return [({}+{}).format(a,b)]                           
TypeError: unsupported operand type(s) for +: 'dict' and 'd
ict'                                 
Please anyone can to me what wrong I am doing?
I want to try:
use .format in + or  *, it that it would be not ok??
is that .format only can be use between "XXX" ????
I also want to try:
print("Love " * {}).format( count)
seem also fail.
Pls advise and much appreciate

Steve Hunter · Accepted Answer

Hi Donald, 
The curly braces are placeholders that are used inside the string to insert the values held by variables, or direct numbers. So, something like:
python
"{} times {} equals {}".format(a, b, a*b)

Depending on the values of a & b, you'd get the output "3 times 4 equals 12". 
For your first code block, there's nothing to create an average yet but we could do something like:
python
def average(a,b):
  ave = (a + b) / 2
  return "The average of {} and {} is {}".format(a, b, ave)
avg = average(3,4)
print (avg)

Here, the value held by a goes in the first {}, b goes in the second {} and the last {} is filled with the value of ave. 
And you second code block could look like:
python
print("Love  * {}").format( count)

For that, I just moved the closing inverted comma so that the {} was inside the string. 
I hope that helps. 
Steve.

Donald Tam · Answer

Thx for help.
it mean that .format(XXX) only can be use inside string.
Noted and thats

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Donald Tam

Donald Tam

using {}.format in function for (a+b) handling

2 Answers

Steve Hunter

Steve Hunter

Donald Tam

Donald Tam