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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 get_known_transports():
 """Return a dictionary of all known transport mechanisms."""

    if not hasattr(get_known_transports, "cache"):
        setattr(
            get_known_transports,
            "cache",
            {
                e.name: e.load()
                for e in pkg_resources.iter_entry_points("workflows.transport")
            },
        )
    return get_known_transports.cache.copy()