How we detect

• an except instruction is immediately followed by a colon, i.e does not specify any exception class name (case of a bare except).
• an except instruction is catching the BaseException class
• an “except Exception:” is in first position or not in last position.

bad

def divide(a, b):
    try:
      result = a / b
    except:
      result = None

  return result

good

def divide(a, b):
    result = None

    try:
        result = a / b
    except ZeroDivisionError:
        print "Type error: division by 0."
    except TypeError:
        # E.g., if b is a string
        print "Type error: division by '{0}'.".format(b)
    except Exception as e:
        # handle any other exception
        print "Error '{0}' occured. Arguments {1}.".format(e.message, e.args)
    else:
        # Excecutes if no exception occured
        print "No errors"
    finally:
        # Executes always
        if result is None:
            result = 0

    return result