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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 read_counts(node):
 """Check how many times a variable definition was used. Args: node: An AST to analyze. Returns: A dictionary from assignment nodes to the number of times the assigned to variable was used. """

  cfg.forward(node, cfg.ReachingDefinitions())

  rc = ReadCounts()
  rc.visit(node)
  return rc.n_read