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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_triangles(self, var, coords=None, convert_radian=True, copy=False, src_crs=None, target_crs=None, nans=None, stacklevel=1):
 """ Get the triangles for the variable Parameters var: xarray.Variable or xarray.DataArray The variable to use coords: dict Alternative coordinates to use. If None, the coordinates of the :attr:`ds` dataset are used convert_radian: bool If True and the coordinate has units in 'radian', those are converted to degrees copy: bool If True, vertice arrays are copied src_crs: cartopy.crs.Crs The source projection of the data. If not None, a transformation to the given `target_crs` will be done target_crs: cartopy.crs.Crs The target projection for which the triangles shall be transformed. Must only be provided if the `src_crs` is not None. %(CFDecoder._check_triangular_bounds.parameters.nans)s Returns ------- matplotlib.tri.Triangulation The spatial triangles of the variable Raises ------ ValueError If `src_crs` is not None and `target_crs` is None"""

        warn("The 'get_triangles' method is depreceated and will be removed "
             "soon! Use the 'get_cell_node_coord' method!",
             DeprecationWarning, stacklevel=stacklevel)
        from matplotlib.tri import Triangulation

        def get_vertices(axis):
            bounds = self._check_triangular_bounds(var, coords=coords,
                                                   axis=axis, nans=nans)[1]
            if coords is not None:
                bounds = coords.get(bounds.name, bounds)
            vertices = bounds.values.ravel()
            if convert_radian:
                coord = getattr(self, 'get_' + axis)(var)
                if coord.attrs.get('units') == 'radian':
                    vertices = vertices * 180. / np.pi
            return vertices if not copy else vertices.copy()

        if coords is None:
            coords = self.ds.coords

        xvert = get_vertices('x')
        yvert = get_vertices('y')
        if src_crs is not None and src_crs != target_crs:
            if target_crs is None:
                raise ValueError(
                    "Found %s for the source crs but got None for the "
                    "target_crs!" % (src_crs, ))
            arr = target_crs.transform_points(src_crs, xvert, yvert)
            xvert = arr[:, 0]
            yvert = arr[:, 1]
        triangles = np.reshape(range(len(xvert)), (len(xvert) // 3, 3))
        return Triangulation(xvert, yvert, triangles)