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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 save(self):
 """ Save the current instance to the DB """

        with rconnect() as conn:
            try:
                self.validate()
            except ValidationError as e:
                log.warn(e.messages)
                raise
            except ModelValidationError as e:
                log.warn(e.messages)
                raise
            except ModelConversionError as e:
                log.warn(e.messages)
                raise
            except ValueError as e:
                log.warn(e)
                raise
            except FrinkError as e:
                log.warn(e.messages)
                raise
            except Exception as e:
                log.warn(e)
                raise
            else:
                # If this is a new unsaved object, it'll likely have an
                # id of None, which RethinkDB won't like. So if it's None,
                # generate a UUID for it. If the save fails, we should re-set
                # it to None.
                if self.id is None:
                    self.id = str(uuid.uuid4())
                    log.debug(self.id)

                try:
                    query = r.db(self._db).table(self._table).insert(
                        self.to_primitive(),
                        conflict="replace"
                    )
                    log.debug(query)
                    rv = query.run(conn)
                    # Returns something like this:
                    # {
                    #   u'errors': 0,
                    #   u'deleted': 0,
                    #   u'generated_keys': [u'dd8ad1bc-8609-4484-b6c4-ed96c72c03f2'],
                    #   u'unchanged': 0,
                    #   u'skipped': 0,
                    #   u'replaced': 0,
                    #   u'inserted': 1
                    # }
                    log.debug(rv)
                except Exception as e:
                    log.warn(e)
                    self.id = None
                    raise
                else:
                    return self