import pandas as pd 
  
data = {
    'Name': ['Alice', 'Alice', 'Charlie', 'Charlie'],
    'Age': [25, 30, 35, 40],
    'branch': ['New York', 'Los Angeles', 'Chicago', 'Houston']
}
df = pd.DataFrame(data)
  
# concatenate the string 
df['branch'] = df.groupby(['Name'])['branch'].transform(lambda x : ' '.join(x))    
  
# show the dataframe 
print(df) 

can anyone expain what’s happening when we apply transformation function on result of group by?the output i am getting is