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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 _valid_folder(self, base, name):
 """Return whether a folder can be searched."""


        valid = True
        fullpath = os.path.join(base, name)
        if (
            not self.recursive or
            (
                self.folder_exclude_check is not None and
                not self.compare_directory(fullpath[self._base_len:] if self.dir_pathname else name)
            )
        ):
            valid = False
        if valid and (not self.show_hidden and util.is_hidden(fullpath)):
            valid = False
        return self.on_validate_directory(base, name) if valid else valid