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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 _file_local_or_remote(f, get_retriever):
 """Check for presence of a local or remote file. """

    if os.path.exists(f):
        return f
    integration, config = get_retriever.integration_and_config(f)
    if integration:
        return integration.file_exists(f, config)