डेली एक्विज़िशन कोहॉर्ट असाइन करें

# Define a function that will parse the date
def get_day(x): return dt.datetime(x.year, ____, ____) 

# Create InvoiceDay column
online['____'] = online['____'].apply(____) 

# Group by CustomerID and select the InvoiceDay value
grouping = online.groupby('____')['____'] 

# Assign a minimum InvoiceDay value to the dataset
online['CohortDay'] = grouping.____('____')

# View the top 5 rows
print(online.head())