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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 find_missing_projections(label_list, projections):
 """ Finds all combinations of labels in `label_list` that are not covered by an entry in the dictionary of `projections`. Returns a list containing tuples of uncovered label combinations or en empty list if there are none. All uncovered label combinations are naturally sorted. Each entry in the dictionary of projections represents a single projection that maps a combination of labels (key) to a single new label (value). The combination of labels to be mapped is a tuple of naturally sorted labels that apply to one or more segments simultaneously. By defining a special wildcard projection using `('**',)` is is not required to specify a projection for every single combination of labels. Args: label_list (audiomate.annotations.LabelList):
 The label list to relabel projections (dict):
 A dictionary that maps tuples of label combinations to string labels. Returns: List: List of combinations of labels that are not covered by any projection Example: [('a', 'b'), ('a', 'b', 'c'), ('a', 'c'), ('c',)] """

    unmapped_combinations = set()

    if WILDCARD_COMBINATION in projections:
        return []

    for labeled_segment in label_list.ranges():
        combination = tuple(sorted([label.value for label in labeled_segment[2]]))

        if combination not in projections:
            unmapped_combinations.add(combination)

    return sorted(unmapped_combinations)