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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 connected_emulators(self, host=enums.JLinkHost.USB):
 """Returns a list of all the connected emulators. Args: self (JLink):
 the ``JLink`` instance host (int):
 host type to search (default: ``JLinkHost.USB``) Returns: List of ``JLinkConnectInfo`` specifying the connected emulators. Raises: JLinkException: if fails to enumerate devices. """

        res = self._dll.JLINKARM_EMU_GetList(host, 0, 0)
        if res < 0:
            raise errors.JLinkException(res)

        num_devices = res
        info = (structs.JLinkConnectInfo * num_devices)()
        num_found = self._dll.JLINKARM_EMU_GetList(host, info, num_devices)
        if num_found < 0:
            raise errors.JLinkException(num_found)

        return list(info)[:num_found]