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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 iter_transport_opts(opts):
    '''
    Yield transport, opts for all master configured transports
    '''
    transports = set()

    for transport, opts_overrides in six.iteritems(opts.get('transport_opts', {})):
        t_opts = dict(opts)
        t_opts.update(opts_overrides)
        t_opts['transport'] = transport
        transports.add(transport)
        yield transport, t_opts

    if opts['transport'] not in transports:
        yield opts['transport'], opts