def clean_data(data_in):
    """
    Cleans data in a format which can be conveniently
    used for drawing traces. Takes a dictionary as the
    input, and returns a list in the following format:

    input = {'key': ['a b c']}
    output = [key, [a, b, c]]
    """
    key = list(data_in.keys())[0]
    data_out = [key]
    for i in data_in[key]:
        data_out.append(list(map(float, i.split(" "))))

    return data_out