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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 get_belbio_conf_files():
 """Get belbio configuration from files """


    home = os.path.expanduser("~")
    cwd = os.getcwd()

    belbio_conf_fp, belbio_secrets_fp = "", ""

    env_conf_dir = os.getenv("BELBIO_CONF", "").rstrip("/")

    conf_paths = [
        f"{cwd}/belbio_conf.yaml",
        f"{cwd}/belbio_conf.yml",
        f"{env_conf_dir}/belbio_conf.yaml",
        f"{env_conf_dir}/belbio_conf.yml",
        f"{home}/.belbio/conf",
    ]
    secret_paths = [
        f"{cwd}/belbio_secrets.yaml",
        f"{cwd}/belbio_secrets.yml",
        f"{env_conf_dir}/belbio_secrets.yaml",
        f"{env_conf_dir}/belbio_secrets.yml",
        f"{home}/.belbio/secrets",
    ]

    for fn in conf_paths:
        if os.path.exists(fn):
            belbio_conf_fp = fn
            break
    else:
        log.error(
            "No BELBio configuration file found - please add one (see http://bel.readthedocs.io/en/latest/configuration.html)"
        )

    for fn in secret_paths:
        if os.path.exists(fn):
            belbio_secrets_fp = fn
            break

    return (belbio_conf_fp, belbio_secrets_fp)