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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 fix_file(self, file_name):
 """Apply autopep8 to the diff lines of a file. - Returns the diff between original and fixed file. - If self.in_place then this writes the the fixed code the file_name. - Prints dots to show progress depending on options. """

        # We hope that a CalledProcessError would have already raised
        # during the init if it were going to raise here.
        modified_lines = self.modified_lines(file_name)

        return fix_file(file_name, modified_lines, self.options,
                        in_place=self.in_place, diff=True,
                        verbose=self.verbose, cwd=self.cwd)