Read multiple csv files from a folder in python

Question

I have been trying to read multiple files for a folder:

This is the structure and as you can see there are a couple of csv files

I have been trying to do in multiple ways:

import glob
from csv import reader
import pandas as pd
from pathlib import Path
from Csv_files import *

#First method:
path = 'backend/Csv_files' # use your path
allFiles = glob.glob(path + "/*.csv")
frame = pd.DataFrame()
list_ = []
for file_ in allFiles:
    df = pd.read_csv(file_,index_col=None, header=0)
    list_.append(df)
frame = pd.concat(list_)

#Second method:
files = Path("./backend/Csv_files").rglob("*.csv")
all_csvs = [pd.read_csv(file) for file in files]
all_csvs = pd.concat(all_csvs)
all_csvs

path= "backend/Csv_files/"
all_files= glob.glob(path + "*.csv")

all_files
print(all_files)

li=[]

for files in all_files:
    df= pd.read_csv(files, index_col=None,header=0)
    li.append(df)

df=pd.concat(li,axis=0,ignore_index=True)
df`

And this is the error:

Traceback (most recent call last):
  File "/home/al3x4ndru1/PycharmProjects/Lucia/backend/printing.py", line 14, in <module>
    frame = pd.concat(list_)
  File "/home/al3x4ndru1/PycharmProjects/Lucia/venv/lib/python3.8/site-packages/pandas/util/_decorators.py", line 311, in wrapper
    return func(*args, **kwargs)
  File "/home/al3x4ndru1/PycharmProjects/Lucia/venv/lib/python3.8/site-packages/pandas/core/reshape/concat.py", line 346, in concat
    op = _Concatenator(
  File "/home/al3x4ndru1/PycharmProjects/Lucia/venv/lib/python3.8/site-packages/pandas/core/reshape/concat.py", line 403, in __init__
    raise ValueError("No objects to concatenate")
ValueError: No objects to concatenate