If you want two objects with the same elements but in a different order to compare equal, then the obvious thing to do is compare sorted copies of them - for instance, for the dictionaries represented by your JSON strings a and b:

import json

a = json.loads("""
{
    "errors": [
        {"error": "invalid", "field": "email"},
        {"error": "required", "field": "name"}
    ],
    "success": false
}
""")

b = json.loads("""
{
    "success": false,
    "errors": [
        {"error": "required", "field": "name"},
        {"error": "invalid", "field": "email"}
    ]
}
""")

>>> sorted(a.items()) == sorted(b.items())
False

... but that doesn't work, because in each case, the "errors" item of the top-level dict is a list with the same elements in a different order, and sorted() doesn't try to sort anything except the "top" level of an iterable.

To fix that, we can define an ordered function which will recursively sort any lists it finds (and convert dictionaries to lists of (key, value) pairs so that they're orderable):

def ordered(obj):
    if isinstance(obj, dict):
        return sorted((k, ordered(v)) for k, v in obj.items())
    if isinstance(obj, list):
        return sorted(ordered(x) for x in obj)
    else:
        return obj

If we apply this function to a and b, the results compare equal:

>>> ordered(a) == ordered(b)
True

with open("file1.json", "r") as f1:
    file1 = json.loads(f1.read())
with open("file2.json", "r") as f2:
    file2 = json.loads(f2.read())

for item in file2:
    if item not in file1:
        print(f"Found difference: {item}")
        file1.append(item)

print(f"New file1: {file1}")

Two possible ways :

1. Using the technique mentioned in the comment posted by Josh.
2. Using the technique mentioned here : how to compare 2 json in python.

Given that you have a large file, you are better off using difflib technique described in point 1.

Edit based on response to my below answer:

After some research, it appears that the best way to deal with large data payloads is to process this payload in a streamed manner. This way we ensure a speedy processing of the data keeping in mind the memory usage and performance of the software in general.

Refer to this link that talks about Streaming JSON data objects using Python. Similarly take a look at ijson - this is an iterator based JSON parsing/processing library in python.

Hopefully, this helps you towards identifying a good fit library that will solve your use case