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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 realsorted(seq, key=None, reverse=False, alg=ns.DEFAULT):
 """ Convenience function to properly sort signed floats. A signed float in a string could be "a-5.7". This is a wrapper around ``natsorted(seq, alg=ns.REAL)``. The behavior of :func:`realsorted` for `natsort` version >= 4.0.0 was the default behavior of :func:`natsorted` for `natsort` version < 4.0.0. Parameters seq : iterable The input to sort. key : callable, optional A key used to determine how to sort each element of the sequence. It is **not** applied recursively. It should accept a single argument and return a single value. reverse : {{True, False}}, optional Return the list in reversed sorted order. The default is `False`. alg : ns enum, optional This option is used to control which algorithm `natsort` uses when sorting. For details into these options, please see the :class:`ns` class documentation. The default is `ns.REAL`. Returns ------- out : list The sorted input. See Also -------- index_realsorted : Returns the sorted indexes from `realsorted`. Examples -------- Use `realsorted` just like the builtin `sorted`:: [{u}'num2', {u}'num5.3', {u}'num5.10', {u}'num-3'] [{u}'num-3', {u}'num2', {u}'num5.10', {u}'num5.3'] """

    return natsorted(seq, key, reverse, alg | ns.REAL)