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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 find_children(self):
 """Take a tree and set the children according to the parents. Takes a tree structure which lists the parents of each vertex and computes the children for each vertex and places them in."""

        for i in range(len(self.vertices)):
            self.vertices[i].children = []
        for i in range(len(self.vertices)):
            for parent in self.vertices[i].parents:
                if i not in self.vertices[parent].children:
                    self.vertices[parent].children.append(i)