apt-get install python-pysnmp4=4.2.2-1 python-pyasn1=0.1.4-0ubuntu1

Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following package was automatically installed and is no longer required:
  python-support
Use 'apt-get autoremove' to remove them.
Suggested packages:
  doc-base python-pysnmp4-doc
Recommended packages:
  python-pysnmp4-mibs python-pysnmp4-apps python-twisted
The following packages will be REMOVED:
  python-pysnmp-common
The following packages will be upgraded:
  python-pyasn1 python-pysnmp4
2 upgraded, 0 newly installed, 1 to remove and 387 not upgraded.
Need to get 0 B/187 kB of archives.
After this operation, 76.8 kB of additional disk space will be used.
Do you want to continue [Y/n]? 
(Reading database ... 22450 files and directories currently installed.)
Preparing to replace python-pyasn1 0.0.11a-1ubuntu1 (using .../python-pyasn1_0.1.4-0ubuntu1_all.deb) ...
Unpacking replacement python-pyasn1 ...
dpkg: python-pysnmp-common: dependency problems, but removing anyway as you requested:
 python-pysnmp4 depends on python-pysnmp-common (>= 4.1.9a-2~); however:
  Package python-pysnmp-common is to be removed.
(Reading database ... 22454 files and directories currently installed.)
Removing python-pysnmp-common ...
Processing triggers for python-support ...
(Reading database ... 22446 files and directories currently installed.)
Preparing to replace python-pysnmp4 4.1.9a-2ubuntu1 (using .../python-pysnmp4_4.2.2-1_all.deb) ...
Unpacking replacement python-pysnmp4 ...
Processing triggers for python-support ...
Setting up python-pyasn1 (0.1.4-0ubuntu1) ...
Setting up python-pysnmp4 (4.2.2-1) ...