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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 project_data_source_path(cls, project, data_source):
 """Return a fully-qualified project_data_source string."""

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