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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 dfa_to_json(dfa: dict, name: str, path: str = './'):
 """ Exports a DFA to a JSON file. If *path* do not exists, it will be created. :param dict dfa: DFA to export; :param str name: name of the output file; :param str path: path where to save the JSON file (default: working directory) """

    out = {
        'alphabet': list(dfa['alphabet']),
        'states': list(dfa['states']),
        'initial_state': dfa['initial_state'],
        'accepting_states': list(dfa['accepting_states']),
        'transitions': list()
    }

    for t in dfa['transitions']:
        out['transitions'].append(
            [t[0], t[1], dfa['transitions'][t]])

    if not os.path.exists(path):
        os.makedirs(path)
    file = open(os.path.join(path, name + '.json'), 'w')
    json.dump(out, file, sort_keys=True, indent=4)
    file.close()