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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 analyse_text(text):
 """ Recognize JCL job by header. """

        result = 0.0
        lines = text.split('\n')
        if len(lines) > 0:
            if JclLexer._JOB_HEADER_PATTERN.match(lines[0]):
                result = 1.0
        assert 0.0 <= result <= 1.0
        return result