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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 filter_composite_from_subgroups(s):
 """ Given a sorted list of subgroups, return a string appropriate to provide as the a composite track's `filterComposite` argument 'dimA dimB' Parameters s : list A list representing the ordered subgroups, ideally the same list provided to `dimensions_from_subgroups`. The values are not actually used, just the number of items. """

    dims = []
    for letter, sg in zip('ABCDEFGHIJKLMNOPQRSTUVWZ', s[2:]):
        dims.append('dim{0}'.format(letter))
    if dims:
        return ' '.join(dims)