How can I find and read specific values in memory of running WINE application?

I am experimenting with text editors, writing some string and trying to find it in the heap memory and changing it using a python script.

I tried using this code for finding and modifying the value in the memory of a native Leafpad (text editor) program running on Linux. and it works (the value in the heap changed). However, when I try using the script on a WINE application (notepad.exe) it fails finding the value.

How come there is a difference between the WINE and the native Linux application?

What do I need to change in order to make the script work with WINE applications?

This is the script being used for location and modification of a value:

#!/usr/bin/env python3

from sys import argv, exit

def print_usage():
    """Print the usage string if script was used improperly"""
    print('Usage: \
        \t$ {} <pid> <string to read> <string to write>'.format(argv[0]))

def read_write_heap(pid, read_str, write_str):
    """Find @read_str in the heap of @pid and replace it with @write_str"""
        maps_file = open("/proc/{}/maps".format(pid), 'r')
    except IOError as e:
        print("Can't open file /proc/{}/maps: IOError: {}".format(pid, e))
    heap_info = None
    for line in maps_file:
        if 'heap' in line:
            heap_info = line.split()
            print("HEAP: ", line)
    if 'heap' == None:
        print('No heap found!')
    addr = heap_info[0].split('-')
    perms = heap_info[1]
    if 'r' not in perms or 'w' not in perms:
        print('Heap does not have read and/or write permission')
        mem_file = open("/proc/{}/mem".format(pid), 'rb+')
    except IOError as e:
        print("Can't open file /proc/{}/maps: IOError: {}".format(pid, e))
    heap_start = int(addr[0], 16)
    heap_end = int(addr[1], 16)
    heap = mem_file.read(heap_end - heap_start)

    str_offset = heap.find(bytes(read_str, "ASCII"))
    if str_offset < 0:
        print("Can't find {} in /proc/{}/mem".format(read_str, pid))
    mem_file.seek(heap_start + str_offset)

    mem_file.write(bytes(write_str + '\0', "ASCII"))

if (len(argv) == 4):
    pid = argv[1]
    search_str = argv[2]
    replace_str = argv[3]
    read_write_heap(pid, search_str, replace_str)

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