I have below simple program to connect odoo 12 on my local system. I am getting a below-mentioned error. Please advise. 

import xmlrpc.client
import csv

server = "http://localhost:8069"
database = "dietfacts2"
user = "admin"
pwd = "admin"


common = xmlrpc.client.ServerProxy('{}/xmlrpc/2/common'.format(server))
print("Version Details: " , common.version())


uid = common.authenticate(database, user, pwd, {})
print(uid)

Below is the Output: ( I have printed version details.)

Version Details: {'server_version': '12.0', 'server_version_info': [12, 0, 0, 'final', 0, ''], 'server_serie': '12.0', 'protocol_version': 1}

xmlrpc.client.Fault: exp_method_name\n File "/home/odoodev/odoo/odoo/service/common.py", line 30, in exp_authenticate\n res_users = odoo.registry(db)[\'res.users\']\n File "/home/odoodev/odoo/odoo/__init__.py", line 117, in registry\n return modules.registry.Registry(database_name)\n File "/home/odoodev/odoo/odoo/modules/registry.py", line 62, in __new__\n return cls.new(db_name)\n File "/home/odoodev/odoo/odoo/modules/registry.py", line 83, in new\n registry.setup_signaling()\n File "/home/odoodev/odoo/odoo/modules/registry.py", line 361, in setup_signaling\n cr.execute("CREATE SEQUENCE base_registry_signaling INCREMENT BY 1 START WITH 1")\n File "/home/odoodev/odoo/odoo/sql_db.py", line 148, in wrapper\n return f(self, *args, **kwargs)\n File "/home/odoodev/odoo/odoo/sql_db.py", line 225, in execute\n res = self._obj.execute(query, params)\npsycopg2.errors.DuplicateTable: relation "base_registry_signaling" already exists\n\n'>

Main Error npsycopg2.errors.DuplicateTable: relation "base_registry_signaling" already exists