Is it necessary to use custom exception classes?

Question

Python

Please tell me, is it necessary to use my own exception classes in my code? In general, it is good practice to create classes of exceptions and catch them specifically, and not just faceless Exceptions. But I have doubts about the fact that in the code below they will not be of particular use, but the complexity and readability of the code will suffer significantly

class Main:
    def __init__(self, config, credentials, Parser, DB_connection, Sql_requester):
        self.config = config
        self.parser = Parser(self.config)
        self.db_connection = DB_connection(credentials)
        self.sql_requester = Sql_requester
        self.content = []

        try:
            self.get_content()
            self.save_content()
        except Exception as e:
            # write to logger
            print('stop program::', e)

    def get_content(self):
        self.content = self.parser.get_content()

    def save_content(self):
        with self.db_connection as db_connection:
            # some code

if __name__ == '__main__': 
    Main(config, credentials, Parser, DB_connection, Sql_requester)

class Parser:
    def get_content(self):
        try:
            root_html = self.get_html(self.config.url)
            links = self.get_links(root_html)
            content = self.get_content_inner(links)
            return content
        except Exception as e:
            # write to logger
            raise Exception('geting content for parse is failed ')

    def get_html(self, url):
        try:
            # some code
        except Exception as e:
            # write to logger
            raise Exception('getting html of ' + url + ' is failed',)

    def get_links(self, html):
        try:
            # some code
        except:
            # write to logger
            raise Exception('getting links to inner pages is failed')

    def get_content_inner(self, links):
        try:
            # some code
        except:
            # write to logger
            raise Exception('parse of inner page is failed')

        try:
            # some code
        except:
            # write to logger
            raise Exception('formating data of inner page is failed')

In the above code, I tried to throw out all the distracting details. thus the pseudocode turned out. But if anyone is interested, the full code is here

Answer 1

It's good practice to catch as specific exceptions as possible, not Exception. And from this it follows that using your own exception classes is also good.