code: def plot_contour(*args, show=True, **kwargs):
      """
      Draws contour plot of a function
  
      Usage
      =====
  
      Single plot
  
      ``plot_contour(expr, range_x, range_y, **kwargs)``
  
      If the ranges are not specified, then a default range of (-10, 10) is used.
  
      Multiple plot with the same range.
  
      ``plot_contour(expr1, expr2, range_x, range_y, **kwargs)``
  
      If the ranges are not specified, then a default range of (-10, 10) is used.
  
      Multiple plots with different ranges.
  
      ``plot_contour((expr1, range_x, range_y), (expr2, range_x, range_y), ..., **kwargs)``
  
      Ranges have to be specified for every expression.
  
      Default range may change in the future if a more advanced default range
      detection algorithm is implemented.
  
      Arguments
      =========
  
      expr : Expression representing the function along x.
  
      range_x : (:class:`Symbol`, float, float)
          A 3-tuple denoting the range of the x variable, e.g. (x, 0, 5).
  
      range_y : (:class:`Symbol`, float, float)
          A 3-tuple denoting the range of the y variable, e.g. (y, 0, 5).
  
      Keyword Arguments
      =================
  
      Arguments for ``ContourSeries`` class:
  
      n1 : int
          The x range is sampled uniformly at ``n1`` of points.
          This keyword argument replaces ``nb_of_points_x``, which should be
          considered deprecated.
  
      n2 : int
          The y range is sampled uniformly at ``n2`` of points.
          This keyword argument replaces ``nb_of_points_y``, which should be
          considered deprecated.
  
      Aesthetics:
  
      surface_color : Function which returns a float
          Specifies the color for the surface of the plot. See
          :class:`sympy.plotting.Plot` for more details.
  
      If there are multiple plots, then the same series arguments are applied to
      all the plots. If you want to set these options separately, you can index
      the returned ``Plot`` object and set it.
  
      Arguments for ``Plot`` class:
  
      title : str
          Title of the plot.
  
      size : (float, float), optional
          A tuple in the form (width, height) in inches to specify the size of
          the overall figure. The default value is set to ``None``, meaning
          the size will be set by the default backend.
  
      See Also
      ========
  
      Plot, ContourSeries
  
      """
      kwargs.setdefault("show", show)
      return _plot3d_plot_contour_helper(ContourSeries, *args, **kwargs)
  
imports: from sympy.concrete.summations import Sum
  from sympy.core.containers import Tuple
  from sympy.core.expr import Expr
  from sympy.core.function import Function, AppliedUndef
  from sympy.core.symbol import Dummy, Symbol, Wild
  from sympy.external import import_module
  from sympy.functions import sign
  from sympy.plotting.backends.base_backend import Plot
  from sympy.plotting.backends.matplotlibbackend import MatplotlibBackend
  from sympy.plotting.backends.textbackend import TextBackend
  from sympy.plotting.series import LineOver1DRangeSeries, Parametric2DLineSeries, Parametric3DLineSeries, ParametricSurfaceSeries, SurfaceOver2DRangeSeries, ContourSeries
  from sympy.plotting.utils import _check_arguments, _plot_sympify
  from sympy.tensor.indexed import Indexed
  from sympy.plotting.plotgrid import PlotGrid
  from sympy.plotting.series import BaseSeries
  from sympy.plotting.series import Line2DBaseSeries
  from sympy.plotting.series import Line3DBaseSeries
  from sympy.plotting.series import SurfaceBaseSeries
  from sympy.plotting.series import List2DSeries
  from sympy.plotting.series import GenericDataSeries
  from sympy.plotting.series import centers_of_faces
  from sympy.plotting.series import centers_of_segments
  from sympy.plotting.series import flat
  from sympy.plotting.backends.base_backend import unset_show
  from sympy.plotting.backends.matplotlibbackend import _matplotlib_list
  from sympy.plotting.textplot import textplot
label_desc: Use image node_id 12 for calling a global function with example usage: plot_contour() and returns: _plot3d_plot_contour_helper