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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 lookup_token(self, line, col):
 """Given a minified location, this tries to locate the closest token that is a match. Returns `None` if no match can be found. """

        # Silently ignore underflows
        if line < 0 or col < 0:
            return None
        tok_out = _ffi.new('lsm_token_t *')
        if rustcall(_lib.lsm_view_lookup_token, self._get_ptr(),
                    line, col, tok_out):
            return convert_token(tok_out[0])