Installation of psycopg2

Hi Team,

I am trying to connect to PostgreSQL from python.
I have post PostgreSQL gres database version 8.1 and python 3.5 (earlier
version for python 2.4, default installation on unix is also present)

Direct internet connectivity from the organization is not allowed so I have
to go through installation using *setup.py.*

Now, I am facing issue when I run command
*python3.5 /usr/local/bin/psycopg2-2.7.3.2/setup.py install*

running build_ext building 'psycopg2._psycopg' extension creating
build/temp.linux-x86_64-3.5 creating build/temp.linux-x86_64-3.5/psycopg
gcc*** command here In file included from psycopg/psycopgmodule.c:27:
./psycopg/psycopg.h:30:2: error: #error "Psycopg requires PostgreSQL client
library (libpq) >= 9.1"

I checked for path for *pg_config *is there in path variable as '/usr/bin/'.

Can you suggest on below
1. How can I resolve this error?
2. why error say Psycopg instead of Psycopg2
3. will package work with PostgreSQL 8.1 database

Your help will be much appreciated. Let me know if you any further inputs.
Thanks in advance.

Regards
Nitesh Jain