Traceback (most recent call last):
  File "/home/diptanshu/mailman_dev/mailman/.venv/lib/python3.5/site-packages/SQLAlchemy-1.1.5-py3.5-linux-i686.egg/sqlalchemy/dialects/sqlite/pysqlite.py", line 337, in dbapi
    from sqlite3 import dbapi2 as sqlite  # try 2.5+ stdlib name.
  File "/usr/local/lib/python3.5/sqlite3/__init__.py", line 23, in <module>
    from sqlite3.dbapi2 import *
  File "/usr/local/lib/python3.5/sqlite3/dbapi2.py", line 27, in <module>
    from _sqlite3 import *
ImportError: No module named '_sqlite3'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/diptanshu/mailman_dev/mailman/.venv/bin/mailman", line 11, in <module>
    load_entry_point('mailman', 'console_scripts', 'mailman')()
  File "/home/diptanshu/mailman_dev/mailman/src/mailman/bin/mailman.py", line 97, in main
    initialize(config_path)
  File "/home/diptanshu/mailman_dev/mailman/src/mailman/core/initialize.py", line 185, in initialize
    initialize_2(propagate_logs=propagate_logs)
  File "/home/diptanshu/mailman_dev/mailman/src/mailman/core/initialize.py", line 156, in initialize_2
    config.db = getUtility(IDatabaseFactory, utility_name).create()
  File "/home/diptanshu/mailman_dev/mailman/src/mailman/database/factory.py", line 54, in create
    database.initialize()
  File "/home/diptanshu/mailman_dev/mailman/src/mailman/database/base.py", line 106, in initialize
    self.engine = create_engine(url, isolation_level='READ UNCOMMITTED')
  File "/home/diptanshu/mailman_dev/mailman/.venv/lib/python3.5/site-packages/SQLAlchemy-1.1.5-py3.5-linux-i686.egg/sqlalchemy/engine/__init__.py", line 387, in create_engine
    return strategy.create(*args, **kwargs)
  File "/home/diptanshu/mailman_dev/mailman/.venv/lib/python3.5/site-packages/SQLAlchemy-1.1.5-py3.5-linux-i686.egg/sqlalchemy/engine/strategies.py", line 80, in create
    dbapi = dialect_cls.dbapi(**dbapi_args)
  File "/home/diptanshu/mailman_dev/mailman/.venv/lib/python3.5/site-packages/SQLAlchemy-1.1.5-py3.5-linux-i686.egg/sqlalchemy/dialects/sqlite/pysqlite.py", line 339, in dbapi
    raise e
  File "/home/diptanshu/mailman_dev/mailman/.venv/lib/python3.5/site-packages/SQLAlchemy-1.1.5-py3.5-linux-i686.egg/sqlalchemy/dialects/sqlite/pysqlite.py", line 334, in dbapi
    from pysqlite2 import dbapi2 as sqlite
ImportError: No module named 'pysqlite2'