Built-in Exceptions

BaseException
 +-- SystemExit                   # Raised by the sys.exit() function.
 +-- KeyboardInterrupt            # Raised when the user hits the interrupt key (ctrl-c).
 +-- Exception                    # User-defined exceptions should be derived from this class.
      +-- ArithmeticError         # Base class for arithmetic errors such as ZeroDivisionError.
      +-- AssertionError          # Raised by `assert <exp>` if expression returns false value.
      +-- AttributeError          # Raised when object doesn't have requested attribute/method.
      +-- EOFError                # Raised by input() when it hits an end-of-file condition.
      +-- LookupError             # Base class for errors when a collection can't find an item.
      |    +-- IndexError         # Raised when a sequence index is out of range.
      |    +-- KeyError           # Raised when a dictionary key or set element is missing.
      +-- MemoryError             # Out of memory. May be too late to start deleting objects.
      +-- NameError               # Raised when nonexistent name (variable/func/class) is used.
      |    +-- UnboundLocalError  # Raised when local name is used before it's being defined.
      +-- OSError                 # Errors such as FileExistsError/TimeoutError (see #Open).
      |    +-- ConnectionError    # Errors such as BrokenPipeError/ConnectionAbortedError.
      +-- RuntimeError            # Raised by errors that don't fall into other categories.
      |    +-- NotImplementedEr…  # Can be raised by abstract methods or by unfinished code.
      |    +-- RecursionError     # Raised when the maximum recursion depth is exceeded.
      +-- StopIteration           # Raised when an empty iterator is passed to next().
      +-- TypeError               # When an argument of the wrong type is passed to function.
      +-- ValueError              # When argument has the right type but inappropriate value.