Can you explain dry run for this code why is enumerate used?

table_row = []

for row in row_data:
current_row = []
row.data = row.findAll(‘td’,{})
for idx,data in enumerate(row_data):
if idx != 0 and idx != 3:
current_row.append(data.text)
else:
current_row.append(data.text)

table_row.append(current_row)