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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 _simple_clause_to_query(clause):
 """ Convert a clause from the Sacred Web API format to the MongoDB format. :param clause: A clause to be converted. It must have "field", "operator" and "value" fields. :return: A MongoDB clause. """

        # It's a regular clause
        mongo_clause = {}
        value = clause["value"]
        if clause["field"] == "status" and clause["value"] in ["DEAD",
                                                               "RUNNING"]:
            return MongoRunDAO. \
                _status_filter_to_query(clause)
        if clause["operator"] == "==":
            mongo_clause[clause["field"]] = value
        elif clause["operator"] == ">":
            mongo_clause[clause["field"]] = {"$gt": value}
        elif clause["operator"] == ">=":
            mongo_clause[clause["field"]] = {"$gte": value}
        elif clause["operator"] == "<":
            mongo_clause[clause["field"]] = {"$lt": value}
        elif clause["operator"] == "<=":
            mongo_clause[clause["field"]] = {"$lte": value}
        elif clause["operator"] == "!=":
            mongo_clause[clause["field"]] = {"$ne": value}
        elif clause["operator"] == "regex":
            mongo_clause[clause["field"]] = {"$regex": value}
        return mongo_clause