docstr: return v= 0 , nth=1
code: def get_data_boundary(self, side):
      """
      return v= 0 , nth=1
      """
      lon1, lon2, lat1, lat2 = self._extremes
      return dict(
          left=(lon1, 0),
          right=(lon2, 0),
          bottom=(lat1, 1),
          top=(lat2, 1),
      )[side]
  
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import six
  from six.moves import zip
  import numpy
  from matplotlib.transforms import Affine2D, IdentityTransform
  from .None import grid_helper_curvelinear
  from .axislines import AxisArtistHelper, GridHelperBase
  from .axis_artist import AxisArtist
  from .grid_finder import GridFinder
  from .grid_finder import ExtremeFinderSimple
  from .axislines import Axes
  from mpl_toolkits.axes_grid1.parasite_axes import host_axes_class_factory
  import matplotlib.axes
label_desc: Use image node_id 2 for calling the GridHelperCurveLinear obj's underlying member method code with example usage: obj.get_data_boundary(side) and returns: dict