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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 notification_channel_path(cls, project, notification_channel):
 """Return a fully-qualified notification_channel string."""

        return google.api_core.path_template.expand(
            "projects/{project}/notificationChannels/{notification_channel}",
            project=project,
            notification_channel=notification_channel,
        )