input: Write a function to count the occurrences of each item in a given dictionary and return the results. If the dictionary is empty, return an empty dictionary.
  assert item_counts({"apples": 5, "oranges": 6, "bananas": 7})=={"apples": 5, "oranges": 6, "bananas": 7}
  assert item_counts({})=={}
output: def item_counts(d):
      return d