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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 _parse_file(self):
 """Preprocess and parse C file into an AST"""


        # We need to set the CPU type to pull in the right register definitions
        # only preprocess the file (-E) and get rid of gcc extensions that aren't
        # supported in ISO C.
        args = utilities.build_includes(self.arch.includes())

        # args.append('-mcpu=%s' % self.arch.property('chip'))
        args.append('-E')
        args.append('-D__attribute__(x)=')
        args.append('-D__extension__=')
        self.ast = parse_file(self.filepath, use_cpp=True, cpp_path='arm-none-eabi-gcc', cpp_args=args)