text: var assert = require('assert');
  
  var _ = require('lodash');
  
  module.exports = function (symbol, expiry, currency, exchange, multiplier) {
    assert(_.isString(symbol), 'Symbol must be a string.');
    assert(_.isString(expiry), 'Expiry must be a string.');
  
    return {
      secType: 'FUT',
      symbol: symbol,
      expiry: expiry,
      currency: currency || 'USD',
      exchange: exchange || 'ONE',
      multiplier: multiplier
    };
  };
  