Why am I getting AttributeError: Object has no attribute? [closed]

I have a class MyThread. In that, I have a method sample. I am trying to run it from within the same object context. Please have a look at the code:

class myThread (threading.Thread):
    def __init__(self, threadID, name, counter, redisOpsObj):
        threading.Thread.__init__(self)
        self.threadID = threadID
        self.name = name
        self.counter = counter
        self.redisOpsObj = redisOpsObj
        
    def stop(self):
        self.kill_received = True
            
    def sample(self):
        print "Hello"
                
    def run(self):
        time.sleep(0.1)
        print "\n Starting " + self.name
        self.sample()

Looks very simple ain't it. But when I run it I get this error

AttributeError: 'myThread' object has no attribute 'sample' Now I have that method, right there. So what's wrong? Please help

Edit: This is the stack trace

Starting Thread-0

Starting Thread-1
Exception in thread Thread-0:
Traceback (most recent call last):
File "/usr/lib/python2.6/threading.py", line 525, in __bootstrap_inner
self.run()
File "./redisQueueProcessor.py", line 51, in run
self.sample()
AttributeError: 'myThread' object has no attribute 'sample'

Exception in thread Thread-1:
Traceback (most recent call last):
File "/usr/lib/python2.6/threading.py", line 525, in __bootstrap_inner
self.run()
File "./redisQueueProcessor.py", line 51, in run
self.sample()
AttributeError: 'myThread' object has no attribute 'sample'

I am calling it like this

arThreads = []
maxThreads = 2;

for i in range( maxThreads ):
    redisOpsObj = redisOps()
    arThreads.append( myThread(i, "Thread-"+str(i), 10, redisOpsObj) )

Sorry, I can't post the redisOps class code. But I can assure you that it works just fine


Solution 1:

Your indentation is goofed, and you've mixed tabs and spaces. Run the script with python -tt to verify.

Solution 2:

If you’re using python 3+ this may also occur if you’re using private variables that start with double underscore, e.g., self.__yourvariable. Just something to take note of for some of you who may run into this issue.

Solution 3:

These kind of bugs are common when Python multi-threading. What happens is that, on interpreter tear-down, the relevant module (myThread in this case) goes through a sort-of del myThread.

The call self.sample() is roughly equivalent to myThread.__dict__["sample"](self). But if we're during the interpreter's tear-down sequence, then its own dictionary of known types might've already had myThread deleted, and now it's basically a NoneType - and has no 'sample' attribute.

Solution 4:

This may also occur if your using slots in class and have not added this new attribute in slots yet.

class xyz(object):
"""
class description

"""

__slots__ = ['abc', 'ijk']

def __init__(self):
   self.abc = 1
   self.ijk = 2
   self.pqr = 6 # This will throw error 'AttributeError: <name_of_class_object> object has no attribute 'pqr'