TypeError: the JSON object must be str

[0c0c0f]

The target response content:

<pre>
    Traceback (most recent call last):

File "/usr/hdp/3.1.0.0-78/superset/lib/python3.4/site-packages/flask/app.py", line 1982, in wsgi_app
response = self.full_dispatch_request()
File "/usr/hdp/3.1.0.0-78/superset/lib/python3.4/site-packages/flask/app.py", line 1614, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/usr/hdp/3.1.0.0-78/superset/lib/python3.4/site-packages/flask/app.py", line 1517, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/usr/hdp/3.1.0.0-78/superset/lib/python3.4/site-packages/flask/_compat.py", line 33, in reraise
raise value
File "/usr/hdp/3.1.0.0-78/superset/lib/python3.4/site-packages/flask/app.py", line 1612, in full_dispatch_request
rv = self.dispatch_request()
File "/usr/hdp/3.1.0.0-78/superset/lib/python3.4/site-packages/flask/app.py", line 1598, in dispatch_request
return self.view_functionsrule.endpoint
File "/usr/hdp/3.1.0.0-78/superset/lib/python3.4/site-packages/superset/models/core.py", line 883, in wrapper
value = f(*args, **kwargs)
File "/usr/hdp/3.1.0.0-78/superset/lib/python3.4/site-packages/superset/utils.py", line 709, in wraps
return f(self, *args, **kwargs)
File "/usr/hdp/3.1.0.0-78/superset/lib/python3.4/site-packages/superset/views/core.py", line 1146, in import_dashboards
data = json.loads(f.stream.read(), object_hook=utils.decode_dashboards)
File "/usr/hdp/3.1.0.0-78/superset/lib/python3.4/json/init.py", line 312, in loads
s.class.name))
TypeError: the JSON object must be str, not 'bytes'

  </pre>