code: def test_size_dim(self, df, kind, backend):
      plot = df.hvplot("x", "y", s="number", kind=kind)
      opts = Store.lookup_options(backend, plot, "style")
      if backend in ["bokeh", "plotly"]:
          param = "size"
      elif backend == "matplotlib":
          param = "s"
      assert opts.kwargs[param] == "number"
      assert "number" in plot.vdims
  
imports: import hvplot
  import holoviews
  import numpy
  import pandas
  import pytest
  import xarray
  from holoviews import Store
  from holoviews.core.options import Options, OptionTree
label_desc: Use image node_id 5 for calling the TestOptions obj's underlying member method code with example usage: obj.test_size_dim(df, kind, backend) without return types