gpg key error when trying to add a PPA

[Ritesh Raj Sarraf]

I keep getting this error when trying to add the ppa. I realized that my 
key used to sign the CoC was the older one, with which LP created the 
PPA. I have deactivated the old key and signed the CoC with my new key. 
But how do I update the new key to the PPA?


rrs at zan:~/devel/Laptop-Mode-Tools/laptop-mode-tools (ubuntu)$ sudo 
add-apt-repository ppa:rrs/laptop-mode-tools
You are about to add the following PPA to your system:
  PPA for Laptop Mode Tools

This PPA is created for the latest and greatest version of Laptop Mode 
Tools. Please note that this PPA also ships a modified version of 
pm-utils, where all overlapping features have been removed from the 
pm-utils package.
So if you run into power related problems, do not just file a bug report 
on Launchpad. Investigate first.

Use at your own risk.
  More info: https://launchpad.net/~rrs/+archive/laptop-mode-tools
Press [ENTER] to continue or ctrl-c to cancel adding it

Exception in thread Thread-1:
Traceback (most recent call last):
   File "/usr/lib/python3.2/threading.py", line 740, in _bootstrap_inner
     self.run()
   File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 
141, in run
     self.add_ppa_signing_key(self.ppa_path)
   File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 
223, in add_ppa_signing_key
     tmp_keyring, tmp_secret_keyring, signing_key_fingerprint, 
tmp_keyring_dir):
   File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 
145, in _recv_key
     if not verify_keyid_is_v4(signing_key_fingerprint):
   File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 
126, in verify_keyid_is_v4
     return len(signing_key_fingerprint) >= 160/8
TypeError: object of type 'NoneType' has no len()

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