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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(cls, parser, text, pos):
 """Parse InspireKeyword. If the keyword is `texkey`, enable the parsing texkey expression flag, since its value contains ':' which normally isn't allowed. """

        try:
            remaining_text, keyword = parser.parse(text, cls.grammar)
            if keyword.lower() == 'texkey':
                parser._parsing_texkey_expression = True
            return remaining_text, InspireKeyword(keyword)
        except SyntaxError as e:
            parser._parsing_texkey_expression = False
            return text, e