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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 from_unit_to_satoshi(self, value, unit='satoshi'):
 """ Convert a value to satoshis. units can be any fiat currency. By default the unit is satoshi. """

        if not unit or unit == 'satoshi':
            return value
        if unit == 'bitcoin' or unit == 'btc':
            return value * 1e8

        # assume fiat currency that we can convert
        convert = get_current_price(self.crypto, unit)
        return int(value / convert * 1e8)