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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 identify_degenerate_nests(nest_spec):
 """ Identify the nests within nest_spec that are degenerate, i.e. those nests with only a single alternative within the nest. Parameters nest_spec : OrderedDict. Keys are strings that define the name of the nests. Values are lists of alternative ids, denoting which alternatives belong to which nests. Each alternative id must only be associated with a single nest! Returns ------- list. Will contain the positions in the list of keys from `nest_spec` that are degenerate. """

    degenerate_positions = []
    for pos, key in enumerate(nest_spec):
        if len(nest_spec[key]) == 1:
            degenerate_positions.append(pos)
    return degenerate_positions