code: def setUp(self):
      Store.current_backend = "matplotlib"
      self.expected = {
          "Image": {
              "plot": {"fig_size": 150},
              "style": {"cmap": "Blues"},
          }
      }
  
imports: import numpy
  from holoviews import Curve, HoloMap, Image, Overlay
  from holoviews.core.options import Store, StoreOptions
  from holoviews.element.comparison import ComparisonTestCase
  from holoviews.plotting import mpl
label_desc: Use image node_id 1 for calling the TestStoreOptionsMerge obj's underlying member method code with example usage: obj.setUp() without return types