<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _get_first(self, keys, default=None):
 """ For given keys, return value for first key that isn't ``None``. If such a key is not found, ``default`` is returned. """

        d = self.device
        for k in keys:
            v = d.get(k)
            if not v is None:
                return v
        return default