How do I handle user defined exceptions in Python? -

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if have error module defined containing application defined exceptions like:

class error(exception):         pass  class noschemaversion(error):         def __init__(self):                 self.code = 1                 self.msg  = "no schema version specified"         pass   class nomsgtype(error):         def __init__(self):                 self.code = 2                 self.msg = "no message type specified"         pass

how handle specific exceptions when raised. tried like:

import error errors = error.error()  try:    <do stuff> except errors.nomsgtype:    <stuff>

but message:

attributeerror: 'error' object has no attribute 'nomsgtype'

what doing wrong?

error.error() (stored in error) constructs new value of error class, nomsgtype separate class isn't part of error, , error.nomsgtype doesn't exist. catch nomsgtype, should write except error.nomsgtype:.


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