Merge branch 'i162_rt130_channels' into i162_show_GPS_clock_0_when_no_data

sohstationviewer/view/plotting/plotting_widget/plotting_axes.py

@@ -2,6 +2,7 @@ from typing import List, Optional, Dict
 
 import numpy as np
 from matplotlib.axes import Axes
+from matplotlib.text import Text
 from matplotlib.patches import ConnectionPatch, Rectangle
 from matplotlib.ticker import AutoMinorLocator
 from matplotlib import pyplot as pl
@@ -154,7 +155,7 @@ class PlottingAxes:
         return ax
 
     def create_sample_no_label(self, ax: Axes, pos_y: float,
-                               sample_no: int, color: str) -> None:
+                               sample_no: int, color: str) -> Optional[Text]:
         """
         Create label to display sample number
         :param ax: the axes of the label