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