input: Write a function to compute the sum of two variables and store the result in a third variable. The function should then print the result. If either of the inputs are not numerical, the function should return a message indicating invalid input.
  assert compute_sum(5, 8)==13
  assert compute_sum(0, 0)==0
  assert compute_sum(-5, 5)==0
  assert compute_sum("5", 8)=="Invalid input: non-numeric value provided."
  assert compute_sum(5, "8")=="Invalid input: non-numeric value provided."
output: def compute_sum(a, b):
      if not isinstance(a, (int, float)) or not isinstance(b, (int, float)):
          return "Invalid input: non-numeric value provided."
      result = a + b
      return result