preprocessor.py

import re 
import pandas as pd


def preprocess(data):

    pattern='\d{1,2}/\d{1,2}/\d{1,2},\s\d{1,2}:\d{1,2}\s\w[A-M]\s-'
    message=re.split(pattern,data)[1:]
    dates=re.findall(pattern,data)
 
    df=pd.DataFrame({'user_message':message,'message_date':dates})
 
    df.head()

    users = []
    messages = []
    for message in df['user_message']:
            entry = re.split('([\w\W]+?):\s', message)
            if entry[1:]:  # user name
                users.append(entry[1])
                messages.append(" ".join(entry[2:]))
            else:
                users.append('group_notification')
                messages.append(entry[0])

    df['user'] = users
    df['message'] = messages
    df.drop(columns=['user_message'], inplace=True)
    df=df.drop(df[df['user']=='group_notification'].index)
    df=df.drop(df[df['message']=='<Media omitted>'].index)
    
    dates=[]
    time=[]
    dateTime=[]
    for i in df['message_date']:
        temp=re.findall('\d{1,2}/\d{1,2}/\d{2}',i)
        temp2=re.findall('\s\d{1,2}:\d{1,2}\s',i)
       
        dates.append(temp[0])
        time.append(temp2[0])
        dateTime.append(temp[0]+temp2[0])
   
    df['date_time']=dateTime
    df.drop(columns=['message_date'], inplace=True)

    df['date']=pd.to_datetime(df['date_time'])
    

    df['only_date'] = df['date'].dt.date
    df['year'] = df['date'].dt.year
    df['month_num'] = df['date'].dt.month
    df['month'] = df['date'].dt.month_name()
    df['day'] = df['date'].dt.day
    df['day_name'] = df['date'].dt.day_name()
    df['hour'] = df['date'].dt.hour
    df['minute'] = df['date'].dt.minute
    print(df.head())
    return df