Is the server running on host "localhost"?

Question

I have an issue with postgresql. I saw some posts editing pg_hba.conf but it doesn't work.

Here the issue :

sqlalchemy.exc.OperationalError: (psycopg2.OperationalError) could not connect to server: Connection refused (0x0000274D/10061)
        Is the server running on host "localhost" (::1) and accepting
        TCP/IP connections on port 32?
could not connect to server: Connection refused (0x0000274D/10061)
        Is the server running on host "localhost" (127.0.0.1) and accepting
        TCP/IP connections on port 32?

And my pg_hba.conf :

# TYPE  DATABASE        USER            ADDRESS                 METHOD

# "local" is for Unix domain socket connections only
local   all             all                                     trust
# IPv4 local connections:
host    all             all             127.0.0.1/32            trust
# IPv6 local connections:
host    all             all             ::1/128                 trust
# Allow replication connections from localhost, by a user with the
# replication privilege.
local   replication     all                                     trust
host    replication     all             127.0.0.1/32            trust
host    replication     all             ::1/128                 trust

I don't understand what is the problem if someone can explain to me.