Access class instance from one file in another file?

I have two files, both are in the same project (part of a web scraping framework). File1 processes items that are generated by File2. In File2 I have a function that prints out some basic stats about the processes (counts of how many items have been generated, etc). I have counts in File1 that I would like to print with the stats from File1 but am unsure of how to do that. Take a look at the example code.

FILE 1:

class Class1(object):
    def __init__(self):
        self.stats = co开发者_JAVA技巧unter("name") #This is the instance that I'd like to use in File2
        self.stats.count = 10

class counter:
    def __init__(self, name):
        self.name = name
        self.count = 0
    def __string__(self):
        message = self.name + self.count
        return message

FILE 2: (this is what I'd like to do)

from project import file1 # this import returns no error

def stats():
    print file1.Class1.stats # This is where I'm trying to get the instance created in Class1 of File2.
    #print file1.Class1.stats.count # Furthermore, it would be nice if this worked too.

ERROR:

exceptions.AttributeError: type object 'Class1' has no attribute 'stats'

I know that both files are running, thus so does the 'stats' instance of the 'counter' class, because of other methods being printed out when running the project (this is just a stripped down example. What am I doing wrong here? Is this possible to do?

---

This is not working because you never instantiate Class1.

__init__ is called when the Class1 is instantiated so Class1.stats is set.

You have 2 options here.

1. instantiate Class1 in file 2 somehow.
2. declare a static method in Class1 that returns the count property.

---

Your terminology is a little mixed up. "both files are running, thus so does the 'stats' instance of the 'counter' class" - stats is a attribute of objects of the counter class. If you want a count of how many instances of the class are created, you should use a class attribute which is something that is bound to your class, and not an instance of it.

class Counter(object):
    count = 0

    def __init__(self, name):
        self.name = name
        Counter.count += 1
        self.id = Counter.count

    def __repr__(self):
        return '<Counter: %s (%d of %d)>' % (
            self.name, self.id, Counter.count)

So then this can be used like so,

>>> foo = Counter('Foo')
>>> print foo
<Counter: Foo (1 of 1)>
>>> bar = Counter('Bar')
>>> print bar
<Counter: Bar (2 of 2)>
>>> print foo
<Counter: Foo (1 of 2)>
>>>

Note that the second time you print foo it has updated the count, but the id remains the same, that is because count is a class attribute, but id is an attribute of the object, so (with this code) the creation of bar doesn't affect the id of foo, but it increments Counter.count.

---

In File1, create an instance of Class1, and use that to get the count.

class Class1(object):
    def __init__(self):
        self.stats = counter()
        self.stats.count = 10

class counter:
    def __init__(self, name):
        self.name = name
        self.count = 0
    def __string__(self):
        message = self.name + self.count
        return message

class_instance = Class1()

In file2, use the created instance:

from project import file1

def stats():
    print file1.class_instance.stats