[Python] zlib.error : Error -3 while decompressing data : incorrect header check

I have a jpg image that is in memory and therefore is in bytes. I then compress it with the following:

zlib.compress(pickle.dumps(self.fileInstance))


I compress it to store it into a MongoDB database. This image is one of the elements in the record that I save. I save the with the following.

list_search_result = list(search_result)
json_search_result = json.dumps(list_search_result, cls=Encoder, indent=2)


I got an error with bytes and Json, so I simply convert the bytes image to a string with the following.

from bson.objectid import ObjectId
import json
import datetime
class Encoder(json.JSONEncoder):
def default(self, obj):
if isinstance(obj, ObjectId):
return str(obj)
elif isinstance(obj, datetime.datetime):
return str(obj)
elif isinstance(obj,bytes):
return str(obj)
return super(Encoder, self).default(obj)


Now, I want to recover the image from the json file. I thought that doing the same steps in the opposite order would work but no.

So here is what I do to store:

image -> pickle -> compress -> str -> json


I thought this would work:

json -> bytes -> decompress -> depickle -> image


I receive the zlib.error : Error -3 during the following:

image = pickle.load(zlib.decompress(attachment[1].encode()))

image = io.BytesIO(image)
dt = Image.open(image)


EDIT:

Okay so I was toying around, and I think the issue might be the .encode(). I start with b" ". After str(b" "), I get "b' '". If I do the .encode(), I get b"b' '". How do I deal with this?

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