Here's how to manipulate CSV files in [[Python]].
### The library
```python
import csv
```
This is the library you'll need for the functions below.
### Iterate through rows in the CSV file
```python
import csv
fields = []
rows = []
with open(filename, 'r') as csvfile:
csvreader = csv.reader(csvfile)
fields = next(csvreader)
for row in csvreader:
rows.append(row)
```
### Write to a CSV file
```python
import csv
fields = ['1', '2', 'tie my shoe']
output_filename = 'output.csv'
with open(output_filename, 'w') as output_file:
writer = csv.writer(output_file)
output_file.write(",".join(fields) + '\n')
writer.writerows(rows)
```