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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 reqSecDefOptParams( self, underlyingSymbol: str, futFopExchange: str, underlyingSecType: str, underlyingConId: int) -> List[OptionChain]: """ Get the option chain. This method is blocking. https://interactivebrokers.github.io/tws-api/options.html Args: underlyingSymbol: Symbol of underlier contract. futFopExchange: Exchange (only for ``FuturesOption``, otherwise leave blank). underlyingSecType: The type of the underlying security, like 'STK' or 'FUT'. underlyingConId: conId of the underlying contract. """

        return self._run(
            self.reqSecDefOptParamsAsync(
                underlyingSymbol, futFopExchange,
                underlyingSecType, underlyingConId))