Hello, i new to python and not 100% where this error is coming from. I am using python 2.7.14. Node.py works with out any issue util i try to enable mining. thank you this project is great and i hope it keeps going.

python mine.py
INFO:apscheduler.scheduler:Adding job tentatively -- it will be properly schedul
ed when the scheduler starts
INFO:apscheduler.scheduler:Added job "mine_for_block" to job store "default"
INFO:apscheduler.scheduler:Scheduler started
DEBUG:apscheduler.scheduler:Looking for jobs to run
INFO:apscheduler.executors.default:Running job "mine_for_block (trigger: date[20
18-03-23 15:28:18 MST], next run at: 2018-03-23 15:28:18 MST)" (scheduled at 201
8-03-23 15:28:18.538000-07:00)
INFO:apscheduler.scheduler:Removed job mining
DEBUG:apscheduler.scheduler:No jobs; waiting until a job is added
ERROR:apscheduler.executors.default:Job "mine_for_block (trigger: date[2018-03-2
3 15:28:18 MST], next run at: 2018-03-23 15:28:18 MST)" raised an exception
Traceback (most recent call last):
File "C:\Python27\lib\site-packages\apscheduler\executors\base.py", line 125,
in run_job
retval = job.func(*job.args, **job.kwargs)
File "mine.py", line 30, in mine_for_block
prev_block = chain.most_recent_block()
File "C:\Users\jcrews-adm\jbc\chain.py", line 78, in most_recent_block
return self.blocks[-1]
IndexError: list index out of range

Changed from
def create_self_hash(self):
sha = hashlib.sha256()
sha.update(self.header_string().encode('utf-8'))
return sha.hexdigest()
to
def create_self_hash(self):
sha = hashlib.sha256()
sha.update(self.header_string().encode('utf-8'))
return sha.hexdigest()

The blockchain itself does appear to be running successfully on my system, but I've run into a number of problems when I run the tests.

• The hashes in test.py all use 5 leading zeroes, but the default value in config.py is 6.
• The with statements on lines 106, 110, 114, and 117 make use of the variables zt, ft, st, and tt, but these variables are not defined until lines 125-128
• Calls to mine.mine_block and mine.mine_from_prev_block fail with ValueError: too many values to unpack, since both return 4 values and test.py tries to assign the results to only 3 variables

All of these are relatively simple fixes, but after I dealt with them I ran into a problem to which the solution was less obvious.

Traceback (most recent call last):  
  File "test.py", line 167, in <module>
    assert new_block == mine_test_block_one
  File "C:\Users\mgplante\blockchain\jbc2\block.py", line 67, in __eq__
    return (self.index == other.index and
AttributeError: 'NoneType' object has no attribute 'index'

It's failing to find a block when the tests assert that it should find a block.

The fact that I'm able to run nodes successfully implies to me that everything is working and that it's just the tests that are wrong, but it's not clear to me how one would go about fixing that.