ImportError: No module named unittest2 on calling openerp_scenario

[esciara]

Trace:

Traceback (most recent call last):
  File "/Users/emmanuelsciara/odoo_scaramouche_bdd/bin/openerp_scenario", line 10, in <module>
    sys.exit(main())
  File "/Users/emmanuelsciara/Documents/Development/git-repos/other-third-party/em_refactored_oerpscenario/oerpscenario/openerp_scenario.py", line 44, in main
    sys.exit(__main__.main(args))
  File "/Users/emmanuelsciara/odoo_scaramouche_bdd/lib/python2.7/site-packages/behave/__main__.py", line 111, in main
    failed = runner.run()
  File "/Users/emmanuelsciara/odoo_scaramouche_bdd/lib/python2.7/site-packages/behave/runner.py", line 659, in run
    return self.run_with_paths()
  File "/Users/emmanuelsciara/odoo_scaramouche_bdd/lib/python2.7/site-packages/behave/runner.py", line 664, in run_with_paths
    self.load_hooks()
  File "/Users/emmanuelsciara/odoo_scaramouche_bdd/lib/python2.7/site-packages/behave/runner.py", line 623, in load_hooks
    exec_file(hooks_path, self.hooks)
  File "/Users/emmanuelsciara/odoo_scaramouche_bdd/lib/python2.7/site-packages/behave/runner.py", line 306, in exec_file
    execfile(filename, globals, locals)
  File "/Users/emmanuelsciara/Documents/Development/git-repos/other-third-party/em_refactored_oerpscenario/features/environment.py", line 8, in <module>
    from support import tools, behave_better
  File "/Users/emmanuelsciara/Documents/Development/git-repos/other-third-party/em_refactored_oerpscenario/features/support/__init__.py", line 2, in <module>
    from support import tools
  File "/Users/emmanuelsciara/Documents/Development/git-repos/other-third-party/em_refactored_oerpscenario/features/support/tools.py", line 93, in <module>
    from unittest2 import TestCase
ImportError: No module named unittest2