import requests
import simplejson as json
from stellar_base.keypair import Keypair
from stellar_base.memo import *
from stellar_base.operation import *

from stellar_base.horizon import Horizon
horizon = Horizon()

class TestMethods:
    def __init__(self):
        kp = Keypair.random()
        self.fee = 100
        self.address = kp.address().decode('ascii')
        self.seed = kp.seed().decode('ascii') or None

        r = requests.get('https://horizon-testnet.stellar.org/friendbot?addr=' + self.address)
        assert 'hash' in json.loads(r.text), "\n" + urlParam + "\n" + r.text

    def make_envelope(self, *args, **kwargs):
        from stellar_base.transaction import Transaction
        from stellar_base.keypair import Keypair
        from stellar_base.transaction_envelope import TransactionEnvelope as Te
        opts = {
            'sequence': horizon.account(self.address)['sequence'],
            'fee': self.fee * len(args)
        }
        for opt, value in kwargs.items():
            opts[opt] = value
        tx = Transaction( source=self.address, opts=opts)
        for count, op in enumerate(args):
            tx.add_operation( operation=op )
        envelope = Te( tx=tx, opts={"network_id": "TESTNET"} )
        signer = Keypair.from_seed( seed=self.seed )
        envelope.sign( keypair=signer )
        envelope_xdr = envelope.xdr()
        print(envelope_xdr)
        return envelope_xdr

    def test_submit(self):
        envelope_xdr = self.make_envelope(Payment({
                'destination': self.address,
                'asset': Asset.native(),
                'amount': 1618
        }))
        response = horizon.submit( envelope_xdr )
        assert 'hash' in response
@@ -20,22 +20,8 @@
 ort 
-simplejson as 
 json

Fix import, simplejson to json