input: Write a function to find the intersection of two sets of integers. The function should take two sets as input and return the set containing elements that are present in both sets.
  def intersection(set1, set2): 
     return set1 & set2
  
  assert intersection({1, 2, 3, 4}, {3, 4, 5, 6})=={3, 4}
  assert intersection({1, 2}, {3, 4, 5})==set()
  assert intersection({1, 2, 3}, {3, 2, 1})=={1, 2, 3}
  assert intersection(set(), {3, 4, 5})==set()
  assert intersection({1, 2, 3}, set())==set()
output: def intersection(set1, set2): 
     return set1 & set2