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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 parity_get_pending_transaction_hash_by_nonce( self, address: AddressHex, nonce: Nonce, ) -> Optional[TransactionHash]: """Queries the local parity transaction pool and searches for a transaction. Checks the local tx pool for a transaction from a particular address and for a given nonce. If it exists it returns the transaction hash. """

        assert self.eth_node is constants.EthClient.PARITY
        # https://wiki.parity.io/JSONRPC-parity-module.html?q=traceTransaction#parity_alltransactions
        transactions = self.web3.manager.request_blocking('parity_allTransactions', [])
        log.debug('RETURNED TRANSACTIONS', transactions=transactions)
        for tx in transactions:
            address_match = to_checksum_address(tx['from']) == address
            if address_match and int(tx['nonce'], 16) == nonce:
                return tx['hash']
        return None