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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 does_keychain_exist(dict_, list_):
 """ Check if a sequence of keys exist in a nested dictionary. Parameters dict_ : Dict[str/int/tuple, Any] list_ : List[str/int/tuple] Returns ------- keychain_exists : bool Examples -------- True False """

    for key in list_:
        if key not in dict_:
            return False
        dict_ = dict_[key]
    return True