Function to count tuple elements

Suppose you are given a tuple containing ints and strings. Write a Python function to return the # of times a given element, n, appears in the tuple.

For example, given the tuple below, where n=3, your function should return 4, since 3 appears 4 times in the tuple.

input:
         n = 3
         my_tuple = 2, 'my_string', 4, 3, 3, 3, 2, 3

output:
         4