[dataformat] Code cleanup

beat/core/dataformat.py

@@ -45,16 +45,12 @@ Forward importing from :py:mod:`beat.backend.python.dataformat`:
 :py:class:`beat.backend.python.dataformat.Storage`
 """
 
-import os
 import copy
-
 import six
-import simplejson
 
 from . import schema
 from . import prototypes
 from . import utils
-from .baseformat import baseformat
 
 from beat.backend.python.dataformat import Storage  # noqa
 from beat.backend.python.dataformat import DataFormat as BackendDataFormat
@@ -132,7 +128,7 @@ class DataFormat(BackendDataFormat):
         if data is None:  # loads prototype and validates it
 
             self.data, self.errors = prototypes.load("dataformat")
-            assert not self.errors, "\n  * %s" % "\n  *".join(self.errors)
+            assert not self.errors, "\n  * %s" % "\n  *".join(self.errors)  # nosec
 
         else: