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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_class_for_interface(interface):
 """ Returns the main bus class for the given interface. :raises: NotImplementedError if the interface is not known :raises: ImportError if there was a problem while importing the interface or the bus class within that """

    # Find the correct backend
    try:
        module_name, class_name = BACKENDS[interface]
    except KeyError:
        raise NotImplementedError("CAN interface '{}' not supported".format(interface))

    # Import the correct interface module
    try:
        module = importlib.import_module(module_name)
    except Exception as e:
        raise ImportError(
            "Cannot import module {} for CAN interface '{}': {}".format(module_name, interface, e)
        )

    # Get the correct class
    try:
        bus_class = getattr(module, class_name)
    except Exception as e:
        raise ImportError(
            "Cannot import class {} from module {} for CAN interface '{}': {}"
                .format(class_name, module_name, interface, e)
        )

    return bus_class