Raised when a model is not found in the path provided by the user.
Raised when no events to be migrated are found.
Raised when a tracker store does not contain any conversations.
Raised when a tracker store does not contain events within a given time range.
Raised if a python package dependency is needed, but not installed.
Raised when publishing of an event fails.
timestamp- Unix timestamp of the event during which publishing fails.
Returns string representation of exception.