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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 should_build(self, fpath, meta):
 """ Checks if the file should be built or not Only skips layouts which are tagged as INCREMENTAL Rebuilds only those files with mtime changed since previous build """

        if meta.get('layout', self.default_template) in self.inc_layout:
            if self.prev_mtime.get(fpath, 0) == os.path.getmtime(fpath):
                return False
            else:
                return True
        return True