class_docstr: Computes a Sankey diagram from a Graph element for internal use in
  the Sankey element constructor.
  
  Adapted from d3-sankey under BSD-3 license.
  
  Source: https://github.com/d3/d3-sankey/tree/v0.12.3
class_docstr_tok: ["Computes","a","Sankey","diagram","from","a","Graph","element","for","internal","use","in","the","Sankey","element","constructor",".","Adapted","from","d3-sankey","under","BSD-3","license",".","Source",":","https",":","\/\/github.com\/d3\/d3-sankey\/tree\/v0.12.3"]
code: def resolveCollisions(self, nodes, alpha, py):
      _, y0, _, y1 = self.p.bounds
      i = len(nodes) // 2
      subject = nodes[i]
      self.resolveCollisionsBottomToTop(
          nodes, subject["y0"] - py, i - 1, alpha, py
      )
      self.resolveCollisionsTopToBottom(
          nodes, subject["y1"] + py, i + 1, alpha, py
      )
      self.resolveCollisionsBottomToTop(
          nodes, y1, len(nodes) - 1, alpha, py
      )
      self.resolveCollisionsTopToBottom(nodes, y0, 0, alpha, py)
  
imports: import math
  from functools import cmp_to_key
  from itertools import cycle
  import numpy
  import param
  from ..core.data import Dataset
  from ..core.dimension import Dimension
  from ..core.operation import Operation
  from ..core.util import get_param_values, unique_array
  from .graphs import EdgePaths, Graph, Nodes
  from .util import quadratic_bezier
label_desc: Use image node_id 17 for calling the _layout_sankey obj's underlying member method code with example usage: obj.resolveCollisions(nodes, alpha, py) without return types