How can I write a python script that accesses a specific google sheets document. I want to be able to iterate over the rows in the sheet.
You'll need to use the Google Sheets API for this, which allows you to interact with the spreadsheet from Python. Here's an example of how you could do it:

```python
from oauth2client.service_account import ServiceAccountCredentials
import gspread
from oauth2client.credentials import Credentials

# Set up credentials
scope = ['https://spreadsheets.google.com/feeds',
         'https://www.googleapis.com/auth/drive']
creds = ServiceAccountCredentials.from_json_keyfile_name('credentials.json', scope)

# Authenticate and get the sheet ID
sheet = gspread.open("My Spreadsheet").get_all_values()["properties"]["id"]

# Iterate through each row in the sheet
for index, row in sheet.iterrows():
    # Get the values from the row
    values = row['values']

    # Do something with the values here...
```
This code uses the gspread library to interact with the Google Sheets API. You'll need to replace "My Spreadsheet" with your actual spreadsheet name and "credentials.json" with the file containing your service account credentials. The scope parameter specifies the scopes you want to access (in this case, only the drive scope is required). Finally, the loop iterates through each row in the sheet and gets the values from the row using the sheet.values property.