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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 as_dict(self, join='.'):
 """ Returns the error as a path to message dictionary. Paths are joined with the ``join`` string. """

        if self.path:
            path = [str(node) for node in self.path]
        else:
            path = ''
        return { join.join(path): self.message }