DRY

>>> def tensquared():
...     return 10 * 10
... 
>>> tensquared()
100
>>> def ninesquared():
...     return 9 * 9
... 
>>> ninesquared()
81
>>> def square_num(num):
...     return num * num
... 
>>> square_num(10)
100
>>> square_num(9)
81
>>> def mul_list_by_2(*args):
...     mul2 = []
...     for i in args:
...             mul2.append(i*2)
...     return mul2
... 
>>> mul_list_by_2(1,2,3,4)
[2, 4, 6, 8]
>>> 
>>> def mul_list_by_3(*args):
...     mul3 = []
...     for i in args:
...             mul3.append(i*3)
...     return mul3
... 
>>> mul_list_by_3(1,2,3,4)
[3, 6, 9, 12]


>>> def multiply_by_2(num):
...     return num * 2
... 
>>> def manipulate_list(instruction, *args):
...     output = []
...     for i in args:
...             output.append(instruction(i))
...     return output
... 
>>> manipulate_list(multiply_by_2,1,2,3,4)
[2, 4, 6, 8]