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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_signin_url(self, service='ec2'):
 """ Get the URL where IAM users can use their login profile to sign in to this account's console. :type service: string :param service: Default service to go to in the console. """

        alias = self.get_account_alias()
        if not alias:
            raise Exception('No alias associated with this account.  Please use iam.create_account_alias() first.')

        return "https://%s.signin.aws.amazon.com/console/%s" % (alias, service)