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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 keys_to_datetime(obj, *keys):
 """ Converts all the keys in an object to DateTime instances. Args: obj (dict):
 the JSON-like ``dict`` object to modify inplace. keys (str):
 keys of the object being converted into DateTime instances. Returns: dict: ``obj`` inplace. True {} True 'two': '2016-06-06T19:41:43.039284'} True datetime.datetime(2016, 6, 6, 19, 41, 43, 39284) '2016-06-06T19:41:43.039284' """

    if not keys:
        return obj
    for k in keys:
        if k not in obj:
            continue
        v = obj[k]
        if not isinstance(v, string_types):
            continue
        obj[k] = parse_datetime(v)
    return obj