How to use 'simple prime number program in python' in Python

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def prime(num):
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    # num is actually a string because input() returns strings. We'll convert it to int
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    num = int(num)
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    if num < 0:
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        print("Negative integers can not be prime")
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        quit()
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    if num is 1:
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        print("1 is neither prime nor composite")
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        # See how I lazily terminated program otherwise it'd forward "None"(default behaviour of python when function
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        # returns nothing) rather than True or False. Which could mess up the program.
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        # If we hit this if statement above statement is printed then program exits.
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        quit()  # Now you don't need to get sys.exit() to exit python has quit to handle the same thing
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    if num in [2, 3]:
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        # if given argument is 2 or 3, it is prime. We used list without defining a variable which is perfectly valid
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        return True
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    if num % 2 == 0:  # excluding all even numbers except two.
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        return False
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    else:
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        # Here we are starting counter variable from 3 in range. Second argument excludes numbers above one third
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        # of the given argument. Third argument in range sets steps to take to 2. This makes loop to iterate odds
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        for x in range(3, int(num/3), 2):
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            # Checking if argument is divisible by counter. % is modulus operator which returns remainder of division
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            if num % x == 0:
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                return False
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    # It's okay to have more than one return statement when program hits return statement it exits the function.
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    return True

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def prime_number_factorisation(n):
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    if n < 2:
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        return [n]
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    i = 2
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    factors = []
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    while i * i <= n:
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        if n % i:
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            i += 1
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        else:
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            n //= i
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            factors.append(i)
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    if n > 1:
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        factors.append(n)
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    return factors