ValueError: time data 'None' does not match format '%Y-%m-%dT%H:%M:%S.%f'

Question

For the node 'TransactionDate' i have a logic before updating it for policy"POL000002NGJ". The logic i am trying to implement is If existing 'TransactionDate' < than today, then add 5 days with current value and parse it to xml.

Transaction Date Format in XML : 2020-03-23T10:56:15.00

Please Note that, If i parsing the DateTime value like below, It works good But i dont want to hardcode the value... I want to Parse it as a string object to handle for any datetime in format ""%Y-%m-%dT%H:%M:%S.%f""...

# <TransactionDate> 
today = datetime.now()
TransactionDate = doc.find('TransactionDate')
Date = '2020-03-24T10:56:15.00' 
previous_update = datetime.strptime(Date, "%Y-%m-%dT%H:%M:%S.%f")

if previous_update < today:
     today = previous_update - timedelta(days=-5)
     TransactionDate = today.strftime("%Y-%m-%dT%H:%M:%S.%f")

Below code while parsing it as a DateTime Object, I have an issue.. I got struck here and referenced other answers in stackoverflow and python forums, But still i got struct up here and unable to resolve the issue...

if any help to fix will be a great helpful. Thanks. Below code using lxml and getting help to support below code will helpful. Because i already completed for other nodes. My understanding is Date variable is calling as None.. But struck here to fix.. Please help..

# <TransactionDate> 
today = datetime.now()
TransactionDate = doc.find('TransactionDate')
Date = str(TransactionDate)
previous_update = datetime.strptime(Date, "%Y-%m-%dT%H:%M:%S.%f")

if previous_update < today:
     today = previous_update - timedelta(days=-5)
     TransactionDate = today.strftime("%Y-%m-%dT%H:%M:%S.%f")

Full Code is Below

from lxml import etree
from datetime import datetime, timedelta
import random, string


doc = etree.parse(r'C:\Users\python.xml') 

# <PolicyId> - Random generated policy number
Policy_Random_Choice = 'POL' + ''.join(random.choices(string.digits, k=6)) + 'NGJ'

# <TransactionDate> 
today = datetime.now()
TransactionDate = doc.find('TransactionDate')
Date = str(TransactionDate)  
previous_update = datetime.strptime(Date, "%Y-%m-%dT%H:%M:%S.%f")

if previous_update < today:
     today = previous_update - timedelta(days=-5)
     TransactionDate = today.strftime("%Y-%m-%dT%H:%M:%S.%f")
                                  
#Parsing the Variables
replacements = [Policy_Random_Choice  , TransactionDate ]

targets = doc.xpath('//ROW[PolicyId="POL000002NGJ"]')
for target in targets:
    target.xpath('./PolicyId')[0].text = replacements[0]
    target.xpath('.//TransactionDate')[0].text = replacements[1]
 
print(etree.tostring(doc).decode())

Sample XML

<TABLE>
   <ROW>
      <PolicyId>POL000002NGJ</PolicyId>
      <BusinessCoverageCode>COV00002D3X1</BusinessCoverageCode>
      <TransactionDate>2020-03-23T10:56:15.00</TransactionDate>
   </ROW>
   <ROW>
      <PolicyId>POL111111NGJ</PolicyId>
      <BusinessCoverageCode>COV00002D3X4</BusinessCoverageCode>
      <TransactionDate>2020-03-23T10:56:15.00</TransactionDate>
   </ROW>
</TABLE>

Answer 1

Maybe the find method is wrong. Try this one

# <TransactionDate> 
today = datetime.now()
TransactionDate = doc.xpath('//ROW/TransactionDate') # Change find to xpath
Date = str(TransactionDate[0].text) # Use the first one
previous_update = datetime.strptime(Date, "%Y-%m-%dT%H:%M:%S.%f")