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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def matches():
 """This resource returns a list of the currently running WvW matches, with the participating worlds included in the result. Further details about a match can be requested using the ``match_details`` function. The response is a list of match objects, each of which contains the following properties: wvw_match_id (string):
 The WvW match id. red_world_id (number):
 The world id of the red world. blue_world_id (number):
 The world id of the blue world. green_world_id (number):
 The world id of the green world. start_time (datetime):
 A timestamp of when the match started. end_time (datetime):
 A timestamp of when the match ends. """

    wvw_matches = get_cached("wvw/matches.json", False).get("wvw_matches")
    for match in wvw_matches:
        match["start_time"] = parse_datetime(match["start_time"])
        match["end_time"] = parse_datetime(match["end_time"])
    return wvw_matches