Python Generator Vs Comprehension And Pass By Reference Vs Value

I have some code that iterates over a string and produces a list of objects from the string, which I'm calling an instance. It looks something like this. from collections import de

Solution 1:

It seems that the issue has to do with how I was initiating my data. I was initiating a defaultdict as a member of the class:

class myClass:
    self.data = defaultdict(str)

    def __init__(self, data):
        for i, instance in enumerate(data.split('\n')):
            # Do something...
            self.data[i] = instance

I changed it to this:

class myClass:

    def __init__(self, data):
        self.data = defaultdict(str)
        for i, instance in enumerate(data.split('\n')):
            # Do something...
            self.data[i] = instance

And that fixed my problem. Would be interested to hear if anyone knows why.