I retrieved the PGP key from the public key server ,Now need help in getting a python method for encryption which can accept this PGP public key .
As i know PGP/Gnupg.py module do not allow me to use encryption/decryption function separately without generating the key.
It seems to me that the easiest approach is use GPGME, which is basically GnuPG wrapped up in a convenient library form (thus the name, GPGME = GnuPG Made Easy). There is a Python wrapper for GPGME named Pyme which will let you do things like import keys, encrypt messages using them, etc, all using the standard PGP formats. There is some basic Pyme documentation online, along with the promise of more complicated examples being included in the source distribution.