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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 del_functions(self, names):
 """Removes the specified function names from the function library. Functions are removed from this instance of the array; all copies and slices of this array will also have the functions removed. Parameters names : (list of) string(s) Name or list of names of the functions to remove. """

        if isinstance(names, string_types):
            names = [names]
        for name in names:
            self._functionlib.pop(name)