Logging is used to track events that happen when an application runs. Logging calls are added to application code to record or log the events and errors that occur during program execution. In Python, the logging module is used to log such events and errors. An event can be described by a message and can optionally contain data specific to the event. Events also have a level or severity assigned by the developer. Logging is very useful for debugging and for tracking any required information.
The Python TypeError: unhashable type: 'list' usually means that a list is being used as a hash argument. This error occurs when trying to hash a list, which is an unhashable object. For example, using a list as a key in a Python dictionary will cause this error since dictionaries only accept hashable data types as a key. The standard way to solve this issue is to cast a list to a tuple, which is a hashable data type.
When a program encounters an exception during execution, it is terminated if the exception is not handled. By handling multiple exceptions, a program can respond to different exceptions without terminating it. In Python, try-except blocks can be used to catch and respond to one or multiple exceptions. In cases where a process raises more than one possible exception, they can all be handled using a single except clause.