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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 recmat2egg(recmat, list_length=None):
 """ Creates egg data object from zero-indexed recall matrix Parameters recmat : list of lists (subs) of lists (encoding lists) of ints or 2D numpy array recall matrix representing serial positions of freely recalled words \ list_length : int The length of each list (e.g. 16) Returns egg : Egg data object egg data object computed from the recall matrix """

        from .egg import Egg as Egg

        pres = [[[str(word) for word in list(range(0,list_length))] for reclist in recsub] for recsub in recmat]
        rec = [[[str(word) for word in reclist if word is not None] for reclist in recsub] for recsub in recmat]

        return Egg(pres=pres,rec=rec)