input: Write a function to count the number of each item in the given dictionary. The function should return the input dictionary as it is. If the dictionary is modified by any means, the test cases will fail.
  assert item_counts({"apples": 5, "oranges": 6, "bananas": 7})=={"apples": 5, "oranges": 6, "bananas": 7}
  assert item_counts({"grapes": 3, "pears": 4, "kiwis": 9})=={"grapes": 3, "pears": 4, "kiwis": 9}
  assert item_counts({})=={}
  assert item_counts({"lemons": 1, "limes": 2})=={"lemons": 1, "limes": 2}
  assert item_counts({"cherries": 10, "blueberries": 15})=={"cherries": 10, "blueberries": 15}
output: def item_counts(d):
      return d