Generate a Python function that takes in a list of numbers and returns the greatest common divisor (GCD) of the list elements.

Input: [25, 15, 20]

Output: def find_GCD(input_list):
gcd = input_list[0]
for num in input_list[1:]:
gcd = find_GCD(gcd, num)
return gcd

def find_GCD(a, b):
while(b != 0):
a, b = b, a%b
return a

Prompt: Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
Generate a Python function that takes in a list of numbers and returns the greatest common divisor (GCD) of the list elements.

### Input:
[25, 15, 20]

### Output:
def find_GCD(input_list):
gcd = input_list[0]
for num in input_list[1:]:
gcd = find_GCD(gcd, num)
return gcd

def find_GCD(a, b):
while(b != 0):
a, b = b, a%b
return a