Challenge: Writing First Function

Define a function named my_first_function that takes three arguments: a, b, and c. The function should return the result of the following mathematical expression: multiply a by 3, multiply b by 2, add these results to c, and then square the sum.

For instance, for the values 5, 4, and 3, the function should return (5×3 + 4×2 + 3)² = 676.