avoid modifying iterable during loop by using list of keys

change elifs to ifs

gstlal-inspiral/bin/gstlal_ll_inspiral_event_plotter

@@ -222,32 +222,37 @@ class EventPlotter(events.EventProcessor):
 				if not event['uploaded']['ranking_data'] and event['ranking_data_path']:
 					self.upload_ranking_data(event)
 					event['uploaded']['ranking_data'] = True
-				elif not event['uploaded']['ranking_plots'] and event['ranking_data_path']:
+				if not event['uploaded']['ranking_plots'] and event['ranking_data_path']:
 					self.upload_ranking_plots(event)
 					event['uploaded']['ranking_plots'] = True
-				elif not event['uploaded']['psd_plots'] and event['psd']:
+				if not event['uploaded']['psd_plots'] and event['psd']:
 					self.upload_psd_plots(event) 
 					event['uploaded']['psd_plots'] = True
-				elif not event['uploaded']['snr_plots']:
+				if not event['uploaded']['snr_plots']:
 					self.upload_snr_plots(event)
 					event['uploaded']['snr_plots'] = True
 
-		# clean out old events
+		# clean out events once all plots are uploaded
+		# and clean out old events
 		current_time = utils.gps_now()
-		for event_key, event in self.events.items():
-			uploaded = event['uploaded']
-			if uploaded['ranking_data'] and uploaded['ranking_plots'] and uploaded['psd_plots'] and uploaded['snr_plots']:
-				event['coinc'].unlink()
-				event['psd'].unlink()
-				self.events.pop(event_key)
-			if current_time - event['time'] >= self.max_event_time:
-				logging.info('removing stale event from {} and bin {}'.format(event['time'], event['bin']))
+		for event_key in list(self.events.keys()):
+			event = self.events[event_key]
+			if self.all_plots_uploaded(event['uploaded']) or current_time - event['time'] >= self.max_event_time:
+				logging.info('removing event from {} and bin {}'.format(event['time'], event['bin']))
 				if event['coinc'] is not None:
 					logging.info('Did not receive path of ranking data file associated with event from {} and bin {}'.format(event['time'], event['bin']))
 					event['coinc'].unlink()
 					event['psd'].unlink()
 				self.events.pop(event_key)
 
+	@staticmethod
+	def all_plots_uploaded(uploaded):
+		"""
+		return True if all plots for 
+		the event have been uploaded
+		"""
+		return uploaded['ranking_data'] and uploaded['ranking_plots'] and uploaded['psd_plots'] and uploaded['snr_plots']
+
 	def upload_file(self, message, filename, tag, contents, graceid):
 		"""
 		upload a file to gracedb