Python | Excel csv File Unicode Issue

There is a python file to extract user’s data from telegram group.
Here is the codes :

from telethon.sync import TelegramClient
from telethon.tl.functions.messages import GetDialogsRequest
from telethon.tl.types import InputPeerEmpty, InputPeerChannel, InputPeerUser
from telethon.errors.rpcerrorlist import PeerFloodError, UserPrivacyRestrictedError
from telethon.tl.functions.channels import InviteToChannelRequest
import sys
import csv
import traceback
import time
import random
import re


api_id = 000000        # YOUR API_ID
api_hash = 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'        # YOUR API_HASH
phone = '[phone]'        # YOUR PHONE NUMBER, INCLUDING COUNTRY CODE
client = TelegramClient(phone, api_id, api_hash)

client.connect()
if not client.is_user_authorized():
    client.send_code_request(phone)
    client.sign_in(phone, input('Enter the code: '))

def add_users_to_group():
    input_file = sys.argv[1]
    users = []
    with open(input_file, encoding='UTF-8') as f:
        rows = csv.reader(f,delimiter=",",lineterminator="n")
        next(rows, None)
        for row in rows:
            user = {}
            user['username'] = row[0]
            try:
                user['id'] = int(row[1])
                user['access_hash'] = int(row[2])
            except IndexError:
                print ('users without id or access_hash')
            users.append(user)

    #random.shuffle(users)
    chats = []
    last_date = None
    chunk_size = 10
    groups=[]

    result = client(GetDialogsRequest(
                offset_date=last_date,
                offset_id=0,
                offset_peer=InputPeerEmpty(),
                limit=chunk_size,
                hash = 0
            ))
    chats.extend(result.chats)

    for chat in chats:
        try:
            if chat.megagroup== True: # CONDITION TO ONLY LIST MEGA GROUPS.
                groups.append(chat)
        except:
            continue

    print('Choose a group to add members:')
    i=0
    for group in groups:
        print(str(i) + '- ' + group.title)
        i+=1

    g_index = input("Enter a Number: ")
    target_group=groups[int(g_index)]
    print('nnGrupo elegido:t' + groups[int(g_index)].title)

    target_group_entity = InputPeerChannel(target_group.id,target_group.access_hash)

    mode = int(input("Enter 1 to add by username or 2 to add by ID: "))

    error_count = 0

    for user in users:
        try:
            print ("Adding {}".format(user['username']))
            if mode == 1:
                if user['username'] == "":
                    continue
                user_to_add = client.get_input_entity(user['username'])
            elif mode == 2:
                user_to_add = InputPeerUser(user['id'], user['access_hash'])
            else:
                sys.exit("Invalid Mode Selected. Please Try Again.")
            client(InviteToChannelRequest(target_group_entity,[user_to_add]))
            print("Waiting 60 Seconds...")
            time.sleep(60)
        except PeerFloodError:
            print("Getting Flood Error from telegram. Script is stopping now. Please try again after some time.")
        except UserPrivacyRestrictedError:
            print("The user's privacy settings do not allow you to do this. Skipping.")
        except:
            traceback.print_exc()
            print("Unexpected Error")
            error_count += 1
            if error_count > 10:
                sys.exit('too many errors')
            continue

def list_users_in_group():
    chats = []
    last_date = None
    chunk_size = 200
    groups=[]
    
    result = client(GetDialogsRequest(
                offset_date=last_date,
                offset_id=0,
                offset_peer=InputPeerEmpty(),
                limit=chunk_size,
                hash = 0
            ))
    chats.extend(result.chats)
    
    for chat in chats:
        try:
            print(chat)
            groups.append(chat)
            # if chat.megagroup== True:
        except:
            continue
    
    print('Choose a group to scrape members from:')
    i=0
    for g in groups:
        print(str(i) + '- ' + g.title)
        i+=1
    
    g_index = input("Enter a Number: ")
    target_group=groups[int(g_index)]

    print('nnGrupo elegido:t' + groups[int(g_index)].title)
    
    print('Fetching Members...')
    all_participants = []
    all_participants = client.get_participants(target_group, aggressive=True)
    
    print('Saving In file...')
    with open("members-" + re.sub("-+","-",re.sub("[^a-zA-Z]","-",str.lower(target_group.title))) + ".csv","w",encoding='UTF-8') as f:
        writer = csv.writer(f,delimiter=",",lineterminator="n")
        writer.writerow(['username','user id', 'access hash','name','group', 'group id'])
        for user in all_participants:
            if user.username:
                username= user.username
            else:
                username= ""
            if user.first_name:
                first_name= user.first_name
            else:
                first_name= ""
            if user.last_name:
                last_name= user.last_name
            else:
                last_name= ""
            name= (first_name + ' ' + last_name).strip()
            writer.writerow([username,user.id,user.access_hash,name,target_group.title, target_group.id])      
    print('Members scraped successfully.')

def printCSV():
    input_file = sys.argv[1]
    users = []
    with open(input_file, encoding='UTF-8') as f:
        rows = csv.reader(f,delimiter=",",lineterminator="n")
        next(rows, None)
        for row in rows:
            user = {}
            user['username'] = row[0]
            user['id'] = int(row[1])
            user['access_hash'] = int(row[2])
            users.append(user)
            print(row)
            print(user)
    sys.exit('FINITO')

# print('Fetching Members...')
# all_participants = []
# all_participants = client.get_participants(target_group, aggressive=True)
print('What do you want to do:')
mode = int(input("Enter n1-List users in a groupn2-Add users from CSV to Group (CSV must be passed as a parameter to the scriptn3-Show CSVnnYour option:  "))

if mode == 1:
    list_users_in_group()
elif mode == 2:
    add_users_to_group()
elif mode == 3:
    printCSV()

After extracting members when i open members--.csv file i see problems on UniCode characters.
How can i fix this issue?
I am using excel 2016

Answer

The problem is not your code, it’s Excel. When Excel opens a file it uses the encoding that is default for your version of Windows, and that encoding is never UTF-8 – it’s one of the many code pages that they invented before Unicode came about.

If you use the text import wizard, there’s an option to select the text encoding, and you can choose UTF-8 there if you want. But that’s a pain to do every time you need to open a CSV.

There’s a way to make Excel recognize that the file is UTF-8 encoded and use it automatically, many Microsoft products use the same trick. If the file starts with a Unicode Byte Order Mark (BOM) U+FEFF encoded in UTF-8 (the 3 byte sequence 0xEF,0xBB,0xBF), Excel will recognize that the file is UTF-8 encoded and override its default. Python will automatically start your file with this BOM sequence if you use the special encoding 'utf_8_sig'.

with open("members-" + re.sub("-+","-",re.sub("[^a-zA-Z]","-",str.lower(target_group.title))) + ".csv","w",encoding='utf_8_sig') as f:

It’s not recommended that you put this special signature at the beginning of every file, only when you know it will be consumed by an application that requires it.