import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
# import chardet  
current_dir =os.path.join(os.path.dirname(os.path.abspath(__file__))) # Get current dir path .\ (Windows) or ./ (Linux)
files_list = os.listdir(path="current_dir ")                                            # Get files list.
data_list = []
for file in  files_list: 
    df = pd.read_csv(file,names = ['Letter','Count'])                              # Get dataframe for each file.
    data_list.append(a)                                                                        # Generate list for graph.
    result(data_list)
print(plt.plot(data_list))                                                                      # Show graph.