how to have a default string argument in function python code example

Example 1: how to set a default parameter in python

def my_function(num1,num2=0):		#if num2 is not given, it will default it to zero
  return num1 + num2

print(my_function(1,2))				#prints out 3
print(my_function(4))				#prints out 4 since num2 got defaulted to 0

Example 2: python function parameters default value

def F(a, b=None):
    if b is None:
        b = []
    b.append(a)
    return b