input: Write a function to determine if two given strings are anagrams. Two strings are considered anagrams if they contain the same characters with the same frequency, irrespective of order. The function should return True if the strings are anagrams, and False otherwise. If either string is empty, return False.
  
  assert is_anagram("abcd", "cbda")==True
  assert is_anagram("silent", "listen")==True
  assert is_anagram("abcd", "abcde")==False
  assert is_anagram("hello", "world")==False
  assert is_anagram("", "test")==False
output: def is_anagram(s1, s2):
      if s1 == "" or s2 == "":
          return False
      return sorted(s1) == sorted(s2)