docstr: Flatten axes, and filter only visible
  
  Parameters
  ----------
  axes : matplotlib Axes object, or its list-like
docstr_tok: ["Flatten","axes",",","and","filter","only","visible","Parameters","--","--","--","--","--","axes",":","matplotlib","Axes","object",",","or","its","list-like"]
code: def _flatten_visible(self, axes):
      """
      Flatten axes, and filter only visible
  
      Parameters
      ----------
      axes : matplotlib Axes object, or its list-like
  
      """
      axes = _flatten(axes)
      axes = [ax for ax in axes if ax.get_visible()]
      return axes
  
imports: import numpy
  import pandas.util.testing
  from pandas_ml.compat import plotting
  from pandas.util.testing import assert_produces_warning, close, RNGContext, assert_index_equal, assert_series_equal, assert_frame_equal, assert_numpy_array_equal
label_desc: Use image node_id 4 for calling the PlottingTestCase obj's underlying member method code with example usage: obj._flatten_visible(axes) and returns: axes