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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 crypto_withdraw(self, amount, currency, crypto_address):
 """ Withdraw funds to a crypto address. Args: amount (Decimal):
 The amount to withdraw currency (str):
 The type of currency (eg. 'BTC') crypto_address (str):
 Crypto address to withdraw to. Returns: dict: Withdraw details. Example:: { "id":"593533d2-ff31-46e0-b22e-ca754147a96a", "amount":"10.00", "currency": "BTC", } """

        params = {'amount': amount,
                  'currency': currency,
                  'crypto_address': crypto_address}
        return self._send_message('post', '/withdrawals/crypto',
                                  data=json.dumps(params))