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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 to_json(self):
 """Serializes all data in this mapreduce spec into json form. Returns: data in json format. """

    mapper_spec = self.mapper.to_json()
    return {
        "name": self.name,
        "mapreduce_id": self.mapreduce_id,
        "mapper_spec": mapper_spec,
        "params": self.params,
        "hooks_class_name": self.hooks_class_name,
    }