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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 _text_file(self, url):
 """return the content of a file"""

        try:
            with open(url, 'r', encoding='utf-8') as file:
                return file.read()
        except FileNotFoundError:
            print('File `{}` not found'.format(url))
            sys.exit(0)