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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Raw Python - Lambda Functions
Step1:  Lambda functions are just anonymous functions and don't need to be created as official functions prior to being used. This makes them useful because they can really help with code readability (if used appropriately). Their true power comes from their expressiveness when performing inline operations.
I'm sure that sounds abstract at this point but I figured it would lay good ground work for our example
Step2:  square every number that is divisible by 2 from 1 to 20
Step3:  That’s a little abstract at this point...
We'll get to those with map, filter, and reduce below 
Now obviously this is not appropriate for everything but I just want you to understand that lambda functions are just anonymous functions.
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Python Code:
x = range(10)
x
[item**2 for item in x]
def square(num):
    return num**2
list(map(square, x))
square_lamb = lambda num: num**2
list(map(square_lamb, x))
Explanation: Raw Python - Lambda Functions
End of explanation
list(map(lambda num: num**2, x))
Explanation: Lambda functions are just anonymous functions and don't need to be created as official functions prior to being used. This makes them useful because they can really help with code readability (if used appropriately). Their true power comes from their expressiveness when performing inline operations.
I'm sure that sounds abstract at this point but I figured it would lay good ground work for our example
End of explanation
[item**2 for item in range(1,20) if item % 2 == 0]
Explanation: square every number that is divisible by 2 from 1 to 20
End of explanation
list(map(lambda z: z**2, filter(lambda z: z % 2 == 0, range(1,20))))
Explanation: That’s a little abstract at this point...
We'll get to those with map, filter, and reduce below 
Now obviously this is not appropriate for everything but I just want you to understand that lambda functions are just anonymous functions.
End of explanation
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