You have a JSON Lines format text file. You need to parse your file line by line:

import json

data = []
with open('file') as f:
    for line in f:
        data.append(json.loads(line))

Each line contains valid JSON, but as a whole, it is not a valid JSON value as there is no top-level list or object definition.

Note that because the file contains JSON per line, you are saved the headaches of trying to parse it all in one go or to figure out a streaming JSON parser. You can now opt to process each line separately before moving on to the next, saving memory in the process. You probably don't want to append each result to one list and then process everything if your file is really big.

If you have a file containing individual JSON objects with delimiters in-between, use How do I use the 'json' module to read in one JSON object at a time? to parse out individual objects using a buffered method.

Just read each line and construct a json object at this time:

with open(file_path) as f:
    for line in f:
        j_content = json.loads(line)

This way, you load proper complete json object (provided there is no \n in a json value somewhere or in the middle of your json object) and you avoid memory issue as each object is created when needed.

There is also this answer.:

https://stackoverflow.com/a/7795029/671543

If your data is exactly in that format, we can edit it into valid JSON.

import json

source = '''\
{
 "A":0,
 "B":2
}{
 "A":3,
 "B":4
}{
 "C":5,
 "D":6
}
'''

fixed = '[' + source.replace('}{', '},{') + ']'
lst = json.loads(fixed)
print(lst)

output

[{'A': 0, 'B': 2}, {'A': 3, 'B': 4}, {'C': 5, 'D': 6}]

This relies on each record being separated by '}{'. If that's not the case, we can use regex to do the search & replace operation.