Problem while install site

while i install an app on new site, by using bench --site erp.X.X install-app erpnext. It give below error:

Traceback (most recent call last):
File “/usr/lib64/python2.7/runpy.py”, line 162, in _run_module_as_main
main”, fname, loader, pkg_name)
File “/usr/lib64/python2.7/runpy.py”, line 72, in _run_code
exec code in run_globals
File “/home/kinzang/erp/apps/frappe/frappe/utils/bench_helper.py”, line 79, in
main()
File “/home/kinzang/erp/apps/frappe/frappe/utils/bench_helper.py”, line 16, in main
click.Group(commands=commands)(prog_name=‘bench’)
File “/home/kinzang/erp/env/lib/python2.7/site-packages/click/core.py”, line 764, in call
return self.main(*args, **kwargs)
File “/home/kinzang/erp/env/lib/python2.7/site-packages/click/core.py”, line 717, in main
rv = self.invoke(ctx)
File “/home/kinzang/erp/env/lib/python2.7/site-packages/click/core.py”, line 1137, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File “/home/kinzang/erp/env/lib/python2.7/site-packages/click/core.py”, line 1137, in invoke
return _process_result(sub_ctx.command.invoke(sub_ctx))
File “/home/kinzang/erp/env/lib/python2.7/site-packages/click/core.py”, line 956, in invoke
return ctx.invoke(self.callback, **ctx.params)
File “/home/kinzang/erp/env/lib/python2.7/site-packages/click/core.py”, line 555, in invoke
return callback(*args, **kwargs)
File “/home/kinzang/erp/env/lib/python2.7/site-packages/click/decorators.py”, line 17, in new_func
return f(get_current_context(), *args, **kwargs)
File “/home/kinzang/erp/apps/frappe/frappe/commands/init.py”, line 24, in _func
ret = f(frappe._dict(ctx.obj), *args, **kwargs)
File “/home/kinzang/erp/apps/frappe/frappe/commands/site.py”, line 149, in install_app
_install_app(app, verbose=context.verbose)
File “/home/kinzang/erp/apps/frappe/frappe/installer.py”, line 99, in install_app
frappe.clear_cache()
File “/home/kinzang/erp/apps/frappe/frappe/init.py”, line 466, in clear_cache
for fn in get_hooks(“clear_cache”):
File “/home/kinzang/erp/apps/frappe/frappe/init.py”, line 771, in get_hooks
hooks = _dict(cache().get_value(“app_hooks”, load_app_hooks))
File “/home/kinzang/erp/apps/frappe/frappe/utils/redis_wrapper.py”, line 68, in get_value
val = generator()
File “/home/kinzang/erp/apps/frappe/frappe/init.py”, line 749, in load_app_hooks
for app in [app_name] if app_name else get_installed_apps(sort=True):
File “/home/kinzang/erp/apps/frappe/frappe/init.py”, line 713, in get_installed_apps
installed = json.loads(db.get_global(“installed_apps”) or “[]”)
File “/home/kinzang/erp/apps/frappe/frappe/database.py”, line 655, in get_global
return self.get_default(key, user)
File “/home/kinzang/erp/apps/frappe/frappe/database.py”, line 667, in get_default
d = self.get_defaults(key, parent)
File “/home/kinzang/erp/apps/frappe/frappe/database.py”, line 673, in get_defaults
defaults = frappe.defaults.get_defaults(parent)
File “/home/kinzang/erp/apps/frappe/frappe/defaults.py”, line 72, in get_defaults
globald = get_defaults_for()
File “/home/kinzang/erp/apps/frappe/frappe/defaults.py”, line 174, in get_defaults_for
defaults = frappe.cache().hget(“defaults”, parent)
File “/home/kinzang/erp/apps/frappe/frappe/utils/redis_wrapper.py”, line 153, in hget
value = super(redis.Redis, self).hget(self.make_key(name), key)
AttributeError: ‘super’ object has no attribute ‘hget’