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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 file_exists(self, subdir, prefix, suffix):
 """Returns true if the resource file exists, else False. Positional arguments: subdir -- sub directory name under the resource's main directory (e.g. css or js, or an empty string if the resource's directory structure is flat). prefix -- file name without the file extension. suffix -- file extension (if self.minify = True, includes .min before the extension). """

        real_path = os.path.join(self.STATIC_DIR, self.DIR, subdir, prefix + suffix)
        return os.path.exists(real_path)