# Import OrderedDict from collections
from collections import OrderedDict

# Create an OrderedDict called: ridership_date
ridership_date = OrderedDict()

# Iterate over the entries
for date, riders in entries:
    # If a key does not exist in ridership_date, set it to 0
    if date not in ridership_date:
        ridership_date[date] = 0
        
    # Add riders to the date key in ridership_date
    ridership_date[date] += riders
    
# Print the first 31 records
print(list(ridership_date.items())[:31])
