fixed matplotlib issue

src/robofish/io/file.py

@@ -37,7 +37,7 @@ import platform
 
 import matplotlib
 import matplotlib.pyplot as plt
-import matplotlib.cm as cm
+import matplotlib.cm
 from matplotlib import animation
 from matplotlib import patches
 
@@ -928,7 +928,7 @@ class File(h5py.File):
         else:
             step_size = poses.shape[1]
 
-        cmap = cm.get_cmap(cmap)
+        cmap = matplotlib.cm.get_cmap(cmap)
 
         x_world, y_world = self.world_size
         if figsize is None: