input: Write a python function to filter strings based on their length.
  assert filter_strings(['apple', 'banana', 'pear', 'kiwi'], 4) == ['apple', 'banana']
  assert filter_strings(['dog', 'cat', 'elephant', 'mouse'], 3) == ['elephant', 'mouse']
  assert filter_strings(['tiny', 'small', 'big', 'large'], 4) == ['small', 'large']
output: def filter_strings(strings, length):
      return [string for string in strings if len(string) > length]