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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 app_profile_path(cls, project, instance, app_profile):
 """Return a fully-qualified app_profile string."""

        return google.api_core.path_template.expand(
            "projects/{project}/instances/{instance}/appProfiles/{app_profile}",
            project=project,
            instance=instance,
            app_profile=app_profile,
        )