code: def currency_multiplier(src_currency, dest_currency):
      'returns equivalent value in USD for an amt of currency_code'
      if src_currency == 'USD':
          return 1.0
      usd_mult = currency_rates()[src_currency]
      if dest_currency == 'USD':
          return usd_mult
      return usd_mult/currency_rates()[dest_currencyf currency_multiplier(src_currency, dest_currency):
      'returns equivalent value in USD for an amt of currency_code'
      if src_currency == 'USD':
          return 1.0
      usd_mult = currency_rates()[src_currency]
      if dest_currency == 'USD':
          return usd_mult
      return usd_mult/currency_rates()[dest_currency]
docs: returns equivalent value in USD for an amt of currency_code