PyUPS setting the transaction refernce

gistfile1.py

from ups import ShipmentConfirm
from lxml.builder import E

shipment_confirm_api = ShipmentConfirm('a', 'b', 'c', 'd')

# Print the value of the TransactionReference 

print etree.tostring(shipment_confirm_api.TransactionReference, pretty_print=True)

"""
Output:

<TransactionReference>
  <CustomerContext>unspecified</CustomerContext>
</TransactionReference>
"""

# Set a value for transaction reference
shipment_confirm_api.TransactionReference = E.TransactionReference(
    E.CustomerContext('1234')
)

# Print the value of the TransactionReference again

print etree.tostring(shipment_confirm_api.TransactionReference, pretty_print=True)

"""
Output:
<TransactionReference>
  <CustomerContext>1234</CustomerContext>
</TransactionReference>
"""