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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 find_next(self, *strings, **kwargs):
 """ From the editor's current cursor position find the next instance of the given string. Args: strings (iterable):
 String or strings to search for Returns: tup (tuple):
 Tuple of cursor position and line or None if not found Note: This function cycles the entire editor (i.e. cursor to length of editor to zero and back to cursor position). """

        start = kwargs.pop("start", None)
        keys_only = kwargs.pop("keys_only", False)
        staht = start if start is not None else self.cursor
        for start, stop in [(staht, len(self)), (0, staht)]:
            for i in range(start, stop):
                for string in strings:
                    if string in self[i]:
                        tup = (i, self[i])
                        self.cursor = i + 1
                        if keys_only: return i
                        return tup