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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 functions(self):
 """ Return a sorted list of the function names available on the object. """

        names = []

        for i, k in enumerate(self.obj):
            if _(self.obj[k]).isCallable():
                names.append(k)

        return self._wrap(sorted(names))