Postgresql - Could not find any downloads

Question

Why this exception generates on apt-get install or on pip :

 root@tameen:/home/tameen/Downloads/postgis-2.0.1# pip install postgresql-2.0.1
    Collecting postgresql-2.0.1
      Could not find any downloads that satisfy the requirement postgresql-2.0.1
      No distributions at all found for postgresql-2.0.1

sudo apt-get install postgresql

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 postgresql : Depends: postgresql-9.4 but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Answer 1

PostgreSQL is a database system, not a Python library. pip is for installing Python libraries only. You will need to install this via your system's package manager.

For instance, if you are on Debian or Ubuntu, you would need to do sudo apt-get install postgresql .