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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 getFieldInfo(fieldnum):
 """Returns a dictionary containing the metadata of a K2 Campaign field. Raises a ValueError if the field number is unknown. Parameters fieldnum : int Returns ------- field : dict The dictionary contains the keys 'ra', 'dec', 'roll' (floats in decimal degrees), 'start', 'stop', (strings in YYYY-MM-DD format) and 'comments' (free text). """

    try:
        info = _getCampaignDict()["c{0}".format(fieldnum)]
        # Print warning messages if necessary
        if "preliminary" in info and info["preliminary"] == "True":
            logger.warning("Warning: the position of field {0} is preliminary. "
                           "Do not use this position for your final "
                           "target selection!".format(fieldnum))
        return info
    except KeyError:
        raise ValueError("Field {0} not set in this version "
                         "of the code".format(fieldnum))