Overcloud deploy fails with invalid json error

Issue

• Failed deploy json syntax error

"Failed to run action [action_ex_id=9fda6c68-ea9f-46fa-af04-d07317c2b0f9, action_cls='<class 'mistral.actions.action_factory.DeployStackAction'>', attributes='{}', params='{u'container': u'overcloud', u'timeout': 100}']\n ERROR: Value must be valid JSON: Ex
tra data: line 1 column 7 - line 1 column 14 (char 6 - 13)",
 u'status': u'FAILED'}
Removing the current plan files