Create function createPlates() to meet the conditions below:

# - Accepts a list of 3-letter strings, and a list of 4-digit strings
# - add a docstring
# - returns a new list representing all possible combinations of EACH
# - 3-letter string and EACH 4-digit numbers with a dash ('-') in between
# --- Example 1: create_plates(["ZQQ", "AEE"], [1234, 4567])
# --- returns the list ["ZQQ-1234","ZQQ-4567","AEE-1234"," AEE-4567"]
# --- Example 2: create_plates(["ZQQ", "BRP", "AEE"], [1234, 4567])
# --- final list:
# --- ["ZQQ-1234","ZQQ-4567","BRP-1234", "BRP-4567","AEE-1234","AEE-4567"] # - return the result