Write a function in Erlang called func that takes a list of tuples and returns a new list consisting of tuples from the original list, for which the first tuple element is smaller than the second one (each tuple in the incoming list consists of only two elements).

For example, if func( [ {1, 2}, {4, 4}, {9, 10} ] ) is called, it returns [ {1, 2}, {9, 10} ]. Do NOT use any list library functions or list comprehension while solving this.