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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 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]