# Function

  • Function is a group of many commands.

  • We had used a lot of function before this lesson. For example,

    len print range and more.

# How to define our own function

  • uses def keyword following with the name of function
def introduce():
    print("Hi, My name is CodeKids. I am 4 years old.")
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OUTPUT

  • Does not have any output? Why? We need to call them.
def introduce():
    print("Hi, My name is CodeKids. I am 4 years old.")
introduce()
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OUTPUT

Hi, My name is CodeKids. I am 4 years old.

# Function parameter(s) and argument(s)

def introduce(name, age):
    print(f"Hi, My name is {name}. I am {age} years old.")

introduce("CodeKids",4)
introduce("CodeKit",5)
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OUTPUT

Hi, My name is CodeKids. I am 4 years old. Hi, My name is CodeKit. I am 5 years old.

# return keyword

  • return keyword is used for returning some values back to somebody who make a call to particular function.
  • Moreover, if the return is executed, the function would be stopped itself.
def my_plus(a, b):
    return a+b

data = my_plus(3, 4)
print(data)

data2 = my_plus("3", "4")
print(data2)
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OUTPUT

7 34

Debugging process



 


def my_plus(a, b):
    return a+b

data = my_plus(3, 4)
print(data)
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3
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5

 





def my_plus(a, b):
    return a+b

data = my_plus(3, 4)
print(data)
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5

my_plus(a, b) => my_plus(3, 4) => a=3, b=4



 




def my_plus(a, b):
    return a+b

data = my_plus(3, 4)
print(data)
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5

a=3, b=4 => return a+b => return 3+4 => return 7





 


def my_plus(a, b):
    return a+b

data = my_plus(3, 4)
print(data)
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5

Therefore, my_plus(3, 4) == 7 => data = my_plus(3, 4) => data = 7


def my_plus(a, b):
    print("HelloWorldddddddd")
    return a+b

data = my_plus(3, 4)
print(data)

data2 = my_plus("3", "4")
print(data2)
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OUTPUT

HelloWorldddddddd 7 HelloWorldddddddd 34

def my_plus(a, b):
    return a+b
    print("HelloWorldddddddd")

data = my_plus(3, 4)
print(data)

data2 = my_plus("3", "4")
print(data2)
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OUTPUT

7 34

# Exercise Book 14.Function