[vis] Fix matplotlib.cm error

phi/vis/_matplotlib/_matplotlib_plots.py

@@ -8,6 +8,7 @@
 from matplotlib import animation
 from matplotlib import rc
 from matplotlib.axes import Axes
+import matplotlib.cm
 from matplotlib.cm import ScalarMappable
 from matplotlib.colors import Normalize
 from matplotlib.ticker import NullFormatter
@@ -498,7 +499,7 @@ def plot(self, data: Field, figure, subplot, space: Box, min_val: float, max_val
         alphas = reshaped_numpy(alpha, [data.shape.without('vector')])
         a = float(alphas[0])
         prev_patches = set(subplot.patches)
-        stream = subplot.streamplot(x, y, u.T, v.T, color=col, cmap=plt.cm.get_cmap())
+        stream = subplot.streamplot(x, y, u.T, v.T, color=col, cmap=matplotlib.cm.get_cmap())
         stream.lines.set_alpha(a)
         new_patches = set(subplot.patches) - prev_patches
         for obj in new_patches:
@@ -872,7 +873,7 @@ def matplotlib_colors(color: Tensor, dims: Shape, default=None) -> Union[list, N
 
 def add_color_bar(axis: Axes, values, min_val, max_val, cmap=None):
     if cmap is None:
-        cmap = plt.cm.get_cmap()
+        cmap = matplotlib.cm.get_cmap()
     figure = axis.figure
     figure_has_color_bar = any(['colorbar' in ax.get_label() for ax in figure.axes])
     is_complex = np.iscomplex(max_val)