'Adds an rdf value to the collection.
Adds an rdf value to the collection. Does not require that the collection
be locked.
Args:
rdf_value: The rdf value to add to the collection. If this value is not
GrrMessage, it will be wrapped into GrrMessage (later when
collection is iterated, this value will still be returned wrapped
in GrrMessage).
timestamp: The timestamp (in microseconds) to store the rdf value
at. Defaults to the current time.
suffix: A \'fractional timestamp\' suffix to reduce the chance of
collisions. Defaults to a random number.
**kwargs: Keyword arguments to pass through to the underlying database
call.
Returns:
The pair (timestamp, suffix) which identifies the value within the
collection.
Raises:
ValueError: rdf_value has unexpected type.'

def Add(self, rdf_value, timestamp=None, suffix=None, **kwargs):

    return self.StaticAdd(self.collection_id, self.token, rdf_value, timestamp=timestamp, suffix=suffix, **kwargs)
