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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 _encode_config(conf_dict):
 """Encode `conf_dict` to string."""

    out = []

    # get variables in order defined in settings._ALLOWED_MERGES
    for var in settings._ALLOWED_MERGES:
        out.append(conf_dict[var])

    # convert bools to chars
    out = map(
        lambda x: "t" if x else "f",
        out
    )

    return "".join(out)