input: Write a python function to calculate the Jaccard similarity between two strings.
  assert get_jaccard_similarity("python programming", "java programming") == 0.3333333333333333
  assert get_jaccard_similarity("hello world", "hello") == 0.5
  assert get_jaccard_similarity("data science", "data analysis") == 0.25
output: def get_jaccard_similarity(str1, str2):
      set1 = set(str1.split())
      set2 = set(str2.split())
      intersection = set1.intersection(set2)
      union = set1.union(set2)
      return len(intersection) / len(union)