Conditional statement between today date and minus 3 months in Python - python-3.x

Question

I am trying to insert 'NULL' values in a table depending on the date.
If the date is between todays date and 3 months backward (which will be february).
Then I want to update the 'NULL' values into each selected columns.
The Traceback is as following:
Traceback (most recent call last):
File "C:\projects\docs\script.py", line 41, in <module>
if dt < date_sql < dr3:
TypeError: '<' not supported between instances of 'datetime.datetime' and 'pyodbc.Row'
Been strugling for a long time, so really appreciate your guidance as I have tried to find a solution.
Python code is:
import pyodbc
from datetime import date, datetime
import dateutil.relativedelta
conn = pyodbc.connect(
r'DRIVER={SQL Server};'
r'SERVER=server;'
r'DATABASE=db;'
)
dt = datetime.today()
dr3 = dt - dateutil.relativedelta.relativedelta(months=3)
print(dr3)
cursor = conn.cursor()
sent_date = cursor.execute("""SELECT TOP 30 sent_date, id
FROM Department.Customer""")
def fetch_date():
for row in sent_date:
r = row
print(r)
return r
date_sql = fetch_date()
if dt < date_sql < dr3:
try:
value = None
cursor.execute("""UPDATE Department.Customer SET name=?, address=?, email=?,
phone=?""", (value, value, value, value))
cursor.commit()
except pyodbc.Error as ex:
print(str(ex))
cursor.rollback()
cursor.close()
Output from print(dr3) is:
2018-02-28 17:19:50.452290
Output from print(r) in fetch_date() function is:
(datetime.datetime(2018, 5, 22, 10, 21, 36), 1)
(datetime.datetime(2018, 5, 22, 10, 21, 36), 2)
(datetime.datetime(2018, 5, 22, 10, 21, 36), 3)
...