def test_stream_threading(self):
bts = self.bts
b = Blockchain(crea_instance=bts)
ops_stream_no_threading = []
opNames = ["transfer", "vote"]
block_num_list2 = []
for op in b.stream(opNames=opNames, start=self.start, stop=self.stop, threading=False):
ops_stream_no_threading.append(op)
if op["block_num"] not in block_num_list2:
block_num_list2.append(op["block_num"])
for n in range(5):
ops_stream = []
block_num_list = []
for op in b.stream(opNames=opNames, start=self.start, stop=self.stop, threading=True, thread_num=8):
ops_stream.append(op)
if op["block_num"] not in block_num_list:
block_num_list.append(op["block_num"])
self.assertEqual(ops_stream[0]["block_num"], ops_stream_no_threading[0]["block_num"])
self.assertEqual(ops_stream[-1]["block_num"], ops_stream_no_threading[-1]["block_num"])
self.assertEqual(len(ops_stream_no_threading), len(ops_stream))
self.assertEqual(len(block_num_list), len(block_num_list2))
for i in range(len(block_num_list)):
self.assertEqual(block_num_list[i], block_num_list2[i])
def profiling(name_list):
stm = Crea()
set_shared_crea_instance(stm)
del stm
print("start")
for name in name_list:
print("account: %s" % (name))
acc = Account(name)
max_index = acc.virtual_op_count()
print(max_index)
stopTime = datetime(2018, 4, 22, 0, 0, 0)
hist_elem = None
for h in acc.history_reverse(stop=stopTime):
hist_elem = h
print(hist_elem)
print("blockchain")
blockchain_object = Blockchain()
current_num = blockchain_object.get_current_block_num()
startBlockNumber = current_num - 20
endBlockNumber = current_num
block_elem = None
for o in blockchain_object.stream(start=startBlockNumber,
stop=endBlockNumber):
print("block %d" % (o["block_num"]))
block_elem = o
print(block_elem)
def test_signing_appbase(self):
b = Blockchain(crea_instance=self.bts)
st = None
for block in b.blocks(start=25304468, stop=25304468):
for trx in block.transactions:
st = Signed_Transaction(trx.copy())
self.assertTrue(st is not None)
def test_stream_batch(self):
bts = self.bts
b = Blockchain(crea_instance=bts)
ops_stream = []
opNames = ["transfer", "vote"]
for op in b.stream(opNames=opNames, start=self.start, stop=self.stop, max_batch_size=self.max_batch_size, threading=False):
ops_stream.append(op)
self.assertTrue(ops_stream[0]["block_num"] >= self.start)
self.assertTrue(ops_stream[-1]["block_num"] <= self.stop)
op_stat = b.ops_statistics(start=self.start, stop=self.stop)
self.assertEqual(op_stat["vote"] + op_stat["transfer"], len(ops_stream))
ops_blocks = []
for op in b.blocks(start=self.start, stop=self.stop, max_batch_size=self.max_batch_size, threading=False):
ops_blocks.append(op)
op_stat4 = {"transfer": 0, "vote": 0}
self.assertTrue(len(ops_blocks) > 0)
for block in ops_blocks:
for tran in block["transactions"]:
for op in tran['operations']:
if isinstance(op, dict) and "type" in op and "value" in op:
op_type = op["type"]
if len(op_type) > 10 and op_type[len(op_type) - 10:] == "_operation":
op_type = op_type[:-10]
if op_type in opNames:
op_stat4[op_type] += 1
elif op[0] in opNames:
op_stat4[op[0]] += 1
self.assertTrue(block.identifier >= self.start)
self.assertTrue(block.identifier <= self.stop)
self.assertEqual(op_stat["transfer"], op_stat4["transfer"])
self.assertEqual(op_stat["vote"], op_stat4["vote"])
def test_stream2(self):
bts = self.bts
b = Blockchain(crea_instance=bts)
stop_block = b.get_current_block_num()
start_block = stop_block - 10
ops_stream = []
for op in b.stream(start=start_block, stop=stop_block):
ops_stream.append(op)
self.assertTrue(len(ops_stream) > 0)
def test_get_all_accounts(self):
bts = self.bts
b = Blockchain(crea_instance=bts)
accounts = []
limit = 200
for acc in b.get_all_accounts(steps=100, limit=limit):
accounts.append(acc)
self.assertEqual(len(accounts), limit)
self.assertEqual(len(set(accounts)), limit)
def test_stream_batch2(self):
bts = self.bts
b = Blockchain(crea_instance=bts)
ops_stream = []
start_block = 25097000
stop_block = 25097100
opNames = ["account_create", "custom_json"]
for op in b.stream(start=int(start_block), stop=int(stop_block), opNames=opNames, max_batch_size=50, threading=False, thread_num=8):
ops_stream.append(op)
self.assertTrue(ops_stream[0]["block_num"] >= start_block)
self.assertTrue(ops_stream[-1]["block_num"] <= stop_block)
op_stat = b.ops_statistics(start=start_block, stop=stop_block)
self.assertEqual(op_stat["account_create"] + op_stat["custom_json"], len(ops_stream))
def test_block_threading(self):
bts = self.bts
b = Blockchain(crea_instance=bts)
blocks_no_threading = []
for block in b.blocks(start=self.start, stop=self.stop, threading=False, thread_num=8):
blocks_no_threading.append(block)
for n in range(5):
blocks = []
for block in b.blocks(start=self.start, stop=self.stop, threading=True, thread_num=8):
blocks.append(block)
for i in range(min(len(blocks), len(blocks_no_threading))):
self.assertEqual(blocks[i]["block_id"], blocks_no_threading[i]["block_id"])
self.assertEqual(len(blocks_no_threading), len(blocks))
def stream_votes(stm, threading, thread_num):
b = Blockchain(crea_instance=stm)
opcount = 0
start_time = time.time()
for op in b.stream(start=23483000,
stop=23485000,
threading=threading,
thread_num=thread_num,
opNames=['vote']):
sys.stdout.write("\r%s" % op['block_num'])
opcount += 1
now = time.time()
total_duration = now - start_time
print(" votes: %d, time %.2f" % (opcount, total_duration))
return opcount, total_duration
def test_blockchain(self, node_param):
if node_param == "instance":
set_shared_crea_instance(self.bts)
o = Blockchain()
self.assertIn(o.crea.rpc.url, self.urls)
with self.assertRaises(RPCConnection):
Blockchain(crea_instance=Crea(
node="https://abc.d", autoconnect=False, num_retries=1))
else:
set_shared_crea_instance(
Crea(node="https://abc.d", autoconnect=False, num_retries=1))
stm = self.bts
o = Blockchain(crea_instance=stm)
self.assertIn(o.crea.rpc.url, self.urls)
with self.assertRaises(RPCConnection):
Blockchain()
def setUpClass(cls):
nodelist = NodeList()
nodelist.update_nodes(crea_instance=Crea(
node=nodelist.get_nodes(exclude_limited=False), num_retries=10))
cls.bts = Crea(node=nodelist.get_nodes(exclude_limited=True),
nobroadcast=True,
keys={"active": wif},
num_retries=10)
b = Blockchain(crea_instance=cls.bts)
num = b.get_current_block_num()
cls.start = num - 25
cls.stop = num
# from getpass import getpass
# self.bts.wallet.unlock(getpass())
set_shared_crea_instance(cls.bts)
def setUpClass(cls):
nodelist = NodeList()
nodelist.update_nodes(crea_instance=Crea(node=nodelist.get_nodes(exclude_limited=False), num_retries=10))
cls.bts = Crea(
node=nodelist.get_nodes(exclude_limited=True),
nobroadcast=True,
timeout=30,
num_retries=30,
)
# from getpass import getpass
# self.bts.wallet.unlock(getpass())
set_shared_crea_instance(cls.bts)
cls.bts.set_default_account("test")
b = Blockchain(crea_instance=cls.bts)
num = b.get_current_block_num()
# num = 23346630
cls.start = num - 25
cls.stop = num
def test_awaitTX(self):
bts = self.bts
b = Blockchain(crea_instance=bts)
trans = {
'ref_block_num':
3855,
'ref_block_prefix':
1730859721,
'expiration':
'2018-03-09T06:21:06',
'operations': [],
'extensions': [],
'signatures': [
'2033a872a8ad33c7d5b946871e4c9cc8f08a5809258355fc909058eac83'
'20ac2a872517a52b51522930d93dd2c1d5eb9f90b070f75f838c881ff29b11af98d6a1b'
]
}
with self.assertRaises(Exception):
b.awaitTxConfirmation(trans)
def setUpClass(cls):
nodelist = NodeList()
nodelist.update_nodes(crea_instance=Crea(node=nodelist.get_nodes(exclude_limited=False), num_retries=10))
cls.bts = Crea(
node=nodelist.get_nodes(exclude_limited=True),
nobroadcast=True,
num_retries=10,
timeout=30,
use_condenser=False,
keys={"active": wif},
)
# from getpass import getpass
# self.bts.wallet.unlock(getpass())
set_shared_crea_instance(cls.bts)
cls.bts.set_default_account("test")
b = Blockchain(crea_instance=cls.bts)
num = b.get_current_block_num()
cls.start = num - 100
cls.stop = num
cls.max_batch_size = 1 # appbase does not support batch rpc calls at the momement (internal error)
def test_hash_op(self):
bts = self.bts
b = Blockchain(crea_instance=bts)
op1 = {
'type': 'vote_operation',
'value': {
'voter': 'ubg',
'author': 'yesslife',
'permlink': 'creait-sandwich-contest-week-25-2da-entry',
'weight': 100
}
}
op2 = [
'vote', {
'voter': 'ubg',
'author': 'yesslife',
'permlink': 'creait-sandwich-contest-week-25-2da-entry',
'weight': 100
}
]
hash1 = b.hash_op(op1)
hash2 = b.hash_op(op2)
self.assertEqual(hash1, hash2)
def test_blockchain(self):
bts = self.bts
b = Blockchain(crea_instance=bts)
num = b.get_current_block_num()
self.assertTrue(num > 0)
self.assertTrue(isinstance(num, int))
block = b.get_current_block()
self.assertTrue(isinstance(block, Block))
self.assertTrue((num - block.identifier) < 3)
block_time = b.block_time(block.identifier)
self.assertEqual(block.time(), block_time)
block_timestamp = b.block_timestamp(block.identifier)
timestamp = int(time.mktime(block.time().timetuple()))
self.assertEqual(block_timestamp, timestamp)
def test_estimate_block_num(self):
bts = self.bts
b = Blockchain(crea_instance=bts)
last_block = b.get_current_block()
num = last_block.identifier
old_block = Block(num - 60, crea_instance=bts)
date = old_block.time()
est_block_num = b.get_estimated_block_num(date, accurate=False)
self.assertTrue((est_block_num - (old_block.identifier)) < 10)
est_block_num = b.get_estimated_block_num(date, accurate=True)
self.assertTrue((est_block_num - (old_block.identifier)) < 2)
est_block_num = b.get_estimated_block_num(date,
estimateForwards=True,
accurate=True)
self.assertTrue((est_block_num - (old_block.identifier)) < 2)
est_block_num = b.get_estimated_block_num(date,
estimateForwards=True,
accurate=False)
def test_wait_for_and_get_block(self):
bts = self.bts
b = Blockchain(crea_instance=bts, max_block_wait_repetition=18)
start_num = b.get_current_block_num()
blocknum = start_num
last_fetched_block_num = None
for i in range(3):
block = b.wait_for_and_get_block(blocknum)
last_fetched_block_num = block.block_num
blocknum = last_fetched_block_num + 1
self.assertEqual(last_fetched_block_num, start_num + 2)
b2 = Blockchain(crea_instance=bts, max_block_wait_repetition=1)
with self.assertRaises(BlockWaitTimeExceeded):
for i in range(300):
block = b2.wait_for_and_get_block(blocknum)
last_fetched_block_num = block.block_num
blocknum = last_fetched_block_num + 2
def benchmark_node(node, how_many_minutes=10, how_many_seconds=30):
block_count = 0
history_count = 0
access_time = 0
follow_time = 0
blockchain_version = u'0.0.0'
successful = True
error_msg = None
start_total = timer()
max_batch_size = None
threading = False
thread_num = 16
authorpermvoter = u"@gtg/crea-pressure-4-need-for-speed|gandalf"
[author, permlink, voter] = resolve_authorpermvoter(authorpermvoter)
authorperm = construct_authorperm(author, permlink)
last_block_id = 19273700
try:
stm = Crea(node=node, num_retries=3, num_retries_call=3, timeout=30)
blockchain = Blockchain(crea_instance=stm)
blockchain_version = stm.get_blockchain_version()
last_block = Block(last_block_id, crea_instance=stm)
stopTime = last_block.time() + timedelta(seconds=how_many_minutes * 60)
total_transaction = 0
start = timer()
for entry in blockchain.blocks(start=last_block_id, max_batch_size=max_batch_size, threading=threading, thread_num=thread_num):
block_no = entry.identifier
block_count += 1
if "block" in entry:
trxs = entry["block"]["transactions"]
else:
trxs = entry["transactions"]
for tx in trxs:
for op in tx["operations"]:
total_transaction += 1
if "block" in entry:
block_time = parse_time(entry["block"]["timestamp"])
else:
block_time = parse_time(entry["timestamp"])
if block_time > stopTime:
last_block_id = block_no
break
if timer() - start > how_many_seconds or quit_thread:
break
except NumRetriesReached:
error_msg = 'NumRetriesReached'
block_count = -1
except KeyboardInterrupt:
error_msg = 'KeyboardInterrupt'
# quit = True
except Exception as e:
error_msg = str(e)
block_count = -1
try:
stm = Crea(node=node, num_retries=3, num_retries_call=3, timeout=30)
account = Account("gtg", crea_instance=stm)
blockchain_version = stm.get_blockchain_version()
start = timer()
for acc_op in account.history_reverse(batch_size=100):
history_count += 1
if timer() - start > how_many_seconds or quit_thread:
break
except NumRetriesReached:
error_msg = 'NumRetriesReached'
history_count = -1
successful = False
except KeyboardInterrupt:
error_msg = 'KeyboardInterrupt'
history_count = -1
successful = False
# quit = True
except Exception as e:
error_msg = str(e)
history_count = -1
successful = False
try:
stm = Crea(node=node, num_retries=3, num_retries_call=3, timeout=30)
account = Account("gtg", crea_instance=stm)
blockchain_version = stm.get_blockchain_version()
start = timer()
Vote(authorpermvoter, crea_instance=stm)
stop = timer()
vote_time = stop - start
start = timer()
Comment(authorperm, crea_instance=stm)
stop = timer()
comment_time = stop - start
start = timer()
Account(author, crea_instance=stm)
stop = timer()
account_time = stop - start
start = timer()
account.get_followers()
stop = timer()
follow_time = stop - start
access_time = (vote_time + comment_time + account_time + follow_time) / 4.0
except NumRetriesReached:
error_msg = 'NumRetriesReached'
access_time = -1
except KeyboardInterrupt:
error_msg = 'KeyboardInterrupt'
# quit = True
except Exception as e:
error_msg = str(e)
access_time = -1
return {'successful': successful, 'node': node, 'error': error_msg,
'total_duration': timer() - start_total, 'block_count': block_count,
'history_count': history_count, 'access_time': access_time, 'follow_time': follow_time,
'version': blockchain_version}
if __name__ == "__main__":
node_setup = 1
threading = True
thread_num = 8
timeout = 10
nodes = NodeList()
nodes.update_nodes(weights={"block": 1})
node_list = nodes.get_nodes()[:5]
vote_result = []
duration = []
stm = Crea(node=node_list, timeout=timeout)
b = Blockchain(crea_instance=stm)
block = b.get_current_block()
block.set_cache_auto_clean(False)
opcount, total_duration = stream_votes(stm, threading, thread_num)
print("Finished!")
block.set_cache_auto_clean(True)
cache_len = len(list(block._cache))
start_time = time.time()
block.clear_cache_from_expired_items()
clear_duration = time.time() - start_time
time.sleep(5)
cache_len_after = len(list(block._cache))
start_time = time.time()
print(str(block._cache))
clear_duration2 = time.time() - start_time
print("Results:")
owner_privkey = owner_key.get_private_key()
memo_privkey = memo_key.get_private_key()
if useWallet:
stm.wallet.addPrivateKey(owner_privkey)
stm.wallet.addPrivateKey(active_privkey)
stm.wallet.addPrivateKey(memo_privkey)
stm.wallet.addPrivateKey(posting_privkey)
else:
stm = Crea(node=testnet_node,
wif={'active': str(active_privkey),
'posting': str(posting_privkey),
'memo': str(memo_privkey)})
account = Account(username, crea_instance=stm)
if account["name"] == "crea":
account.disallow("crea1", permission='posting')
account.allow('crea1', weight=1, permission='posting', account=None)
account.follow("crea1")
elif account["name"] == "crea5":
account.allow('crea4', weight=2, permission='active', account=None)
if useWallet:
stm.wallet.getAccountFromPrivateKey(str(active_privkey))
# stm.create_account("crea1", creator=account, password=password1)
account1 = Account("crea1", crea_instance=stm)
b = Blockchain(crea_instance=stm)
blocknum = b.get_current_block().identifier
account.transfer("crea1", 1, "CBD", "test")
b1 = Block(blocknum, crea_instance=stm)
from __future__ import print_function
import sys
from datetime import timedelta
import time
import io
from crea.blockchain import Blockchain
from crea.utils import parse_time
import logging
log = logging.getLogger(__name__)
logging.basicConfig(level=logging.INFO)
class DemoBot(object):
def comment(self, comment_event):
print('Comment by {} on post {} by {}:'.format(comment_event['author'],
comment_event['parent_permlink'],
comment_event['parent_author']))
print(comment_event['body'])
print()
if __name__ == "__main__":
tb = DemoBot()
blockchain = Blockchain()
for vote in blockchain.stream(opNames=["comment"]):
tb.comment(vote)
import sys
from datetime import timedelta
import time
import io
from crea.blockchain import Blockchain
from crea.utils import parse_time
import logging
log = logging.getLogger(__name__)
logging.basicConfig(level=logging.INFO)
class DemoBot(object):
def vote(self, vote_event):
w = vote_event["weight"]
if w > 0:
print("Vote by", vote_event["voter"], "for", vote_event["author"])
else:
if w < 0:
print("Downvote by", vote_event["voter"], "for",
vote_event["author"])
else:
print("(Down)vote by", vote_event["voter"], "for",
vote_event["author"], "CANCELED")
if __name__ == "__main__":
tb = DemoBot()
blockchain = Blockchain()
for vote in blockchain.stream(opNames=["vote"]):
tb.vote(vote)
for line in file_obj:
elt = loads(unhexlify(line[:-1].encode("latin")))
yield elt
def s_load_binary(file_obj):
'''load contents from file_obj, returning a generator that yields one
element at a time'''
for line in file_obj:
elt = loads(unhexlify(line[:-1]))
yield elt
if __name__ == "__main__":
blockchain = Blockchain()
threading = True
thread_num = 8
cur_block = blockchain.get_current_block()
stop = cur_block.identifier
startdate = cur_block.time() - timedelta(seconds=3600)
start = blockchain.get_estimated_block_num(startdate, accurate=True)
outf = gzip.open('blocks1.pkl', 'w')
blocks = 0
for block in blockchain.stream(opNames=[], start=start, stop=stop, threading=threading, thread_num=thread_num):
s_dump_binary(block, outf)
blocks = blocks + 1
if blocks % 200 == 0:
print(blocks, "blocks streamed")
outf.close()
acc = Account(name, crea_instance=stm)
acc_dict[name] = acc
if clear_acc_cache:
acc.clear_cache()
acc_dict = {}
if clear_all_cache:
clear_cache()
if not shared_instance:
del stm.rpc
if __name__ == "__main__":
stm = Crea()
print("Shared instance: " + str(stm))
set_shared_crea_instance(stm)
b = Blockchain()
account_list = []
for a in b.get_all_accounts(limit=500):
account_list.append(a)
shared_instance = False
clear_acc_cache = False
clear_all_cache = False
node = "https://nodes.creary.net"
n = 3
for i in range(1, n + 1):
print("%d of %d" % (i, n))
profiling(node,
account_list,
shared_instance=shared_instance,
clear_acc_cache=clear_acc_cache,
clear_all_cache=clear_all_cache)
def test_stream(self):
bts = self.bts
start = self.start
stop = self.stop
b = Blockchain(crea_instance=bts)
ops_stream = []
opNames = ["transfer", "vote"]
for op in b.stream(opNames=opNames, start=start, stop=stop):
ops_stream.append(op)
self.assertTrue(len(ops_stream) > 0)
ops_raw_stream = []
opNames = ["transfer", "vote"]
for op in b.stream(opNames=opNames,
raw_ops=True,
start=start,
stop=stop):
ops_raw_stream.append(op)
self.assertTrue(len(ops_raw_stream) > 0)
only_ops_stream = []
opNames = ["transfer", "vote"]
for op in b.stream(opNames=opNames,
start=start,
stop=stop,
only_ops=True):
only_ops_stream.append(op)
self.assertTrue(len(only_ops_stream) > 0)
only_ops_raw_stream = []
opNames = ["transfer", "vote"]
for op in b.stream(opNames=opNames,
raw_ops=True,
start=start,
stop=stop,
only_ops=True):
only_ops_raw_stream.append(op)
self.assertTrue(len(only_ops_raw_stream) > 0)
op_stat = b.ops_statistics(start=start, stop=stop)
op_stat2 = {"transfer": 0, "vote": 0}
for op in ops_stream:
self.assertIn(op["type"], opNames)
op_stat2[op["type"]] += 1
self.assertTrue(op["block_num"] >= start)
self.assertTrue(op["block_num"] <= stop)
self.assertEqual(op_stat["transfer"], op_stat2["transfer"])
self.assertEqual(op_stat["vote"], op_stat2["vote"])
op_stat3 = {"transfer": 0, "vote": 0}
for op in ops_raw_stream:
self.assertIn(op["op"][0], opNames)
op_stat3[op["op"][0]] += 1
self.assertTrue(op["block_num"] >= start)
self.assertTrue(op["block_num"] <= stop)
self.assertEqual(op_stat["transfer"], op_stat3["transfer"])
self.assertEqual(op_stat["vote"], op_stat3["vote"])
op_stat5 = {"transfer": 0, "vote": 0}
for op in only_ops_stream:
self.assertIn(op["type"], opNames)
op_stat5[op["type"]] += 1
self.assertTrue(op["block_num"] >= start)
self.assertTrue(op["block_num"] <= stop)
self.assertEqual(op_stat["transfer"], op_stat5["transfer"])
self.assertEqual(op_stat["vote"], op_stat5["vote"])
op_stat6 = {"transfer": 0, "vote": 0}
for op in only_ops_raw_stream:
self.assertIn(op["op"][0], opNames)
op_stat6[op["op"][0]] += 1
self.assertTrue(op["block_num"] >= start)
self.assertTrue(op["block_num"] <= stop)
self.assertEqual(op_stat["transfer"], op_stat6["transfer"])
self.assertEqual(op_stat["vote"], op_stat6["vote"])
ops_blocks = []
for op in b.blocks(start=start, stop=stop):
ops_blocks.append(op)
op_stat4 = {"transfer": 0, "vote": 0}
self.assertTrue(len(ops_blocks) > 0)
for block in ops_blocks:
for tran in block["transactions"]:
for op in tran['operations']:
if isinstance(op, list) and op[0] in opNames:
op_stat4[op[0]] += 1
elif isinstance(op, dict):
op_type = op["type"]
if len(op_type) > 10 and op_type[len(op_type) -
10:] == "_operation":
op_type = op_type[:-10]
if op_type in opNames:
op_stat4[op_type] += 1
self.assertTrue(block.identifier >= start)
self.assertTrue(block.identifier <= stop)
self.assertEqual(op_stat["transfer"], op_stat4["transfer"])
self.assertEqual(op_stat["vote"], op_stat4["vote"])
ops_blocks = []
for op in b.blocks():
ops_blocks.append(op)
break
self.assertTrue(len(ops_blocks) == 1)
how_many_minutes = 10
how_many_virtual_op = 10000
max_batch_size = None
threading = False
thread_num = 16
nodelist = NodeList()
nodes = nodelist.get_nodes(normal=True, appbase=True, dev=True)
t = PrettyTable([
"node", "10 blockchain minutes", "10000 virtual account op", "version"
])
t.align = "l"
for node in nodes:
print("Current node:", node)
try:
stm = Crea(node=node, num_retries=3)
blockchain = Blockchain(crea_instance=stm)
account = Account("gtg", crea_instance=stm)
virtual_op_count = account.virtual_op_count()
blockchain_version = stm.get_blockchain_version()
last_block_id = 19273700
last_block = Block(last_block_id, crea_instance=stm)
startTime = datetime.now()
stopTime = last_block.time() + timedelta(seconds=how_many_minutes *
60)
ltime = time.time()
cnt = 0
total_transaction = 0
start_time = time.time()