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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 comment(data, what):
 """ Comments line containing `what` in string `data`. Args: data (str):
 Configuration file in string. what (str):
 Line which will be commented out. Returns: str: Configuration file with commented `what`. """

    data = data.splitlines()

    data = map(
        lambda x: "#" + x if x.strip().split() == what.split() else x,
        data
    )

    return "\n".join(data)