return or raise value error in python code example

Example 1: try except python

try:
  print("I will try to print this line of code")
except:
  print("I will print this line of code if an error is encountered")

Example 2: print type of exception python

try:
    someFunction()
except Exception as ex:
    template = "An exception of type {0} occurred. Arguments:\n{1!r}"
    message = template.format(type(ex).__name__, ex.args)
    print (message)

Example 3: python raise exception

# this raises a "NameError"

>>> raise NameError('HiThere')

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: HiThere

Example 4: python: raise error

class MyError(TypeError):
    pass

raise MyError('An error happened')