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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 _update_config_file(username, password, email, url, config_path):
 """Update the config file with the authorization."""

        try:
            # read the existing config
            config = json.load(open(config_path, "r"))
        except ValueError:
            config = dict()

        if not config.get('auths'):
            config['auths'] = dict()

        if not config['auths'].get(url):
            config['auths'][url] = dict()
        encoded_credentials = dict(
            auth=base64.b64encode(username + b':' + password),
            email=email
        )
        config['auths'][url] = encoded_credentials
        try:
            json.dump(config, open(config_path, "w"), indent=5, sort_keys=True)
        except Exception as exc:
            raise exceptions.AnsibleContainerConductorException(
                u"Failed to write registry config to {0} - {1}".format(config_path, exc)
            )