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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 _dump_has(self, service, grep, search):
 """Check if a dump has particular content. :param service: Service to dump. :param grep: Grep for this string. :param search: Check for this substring. :returns: Found or not. """

        dump_grep = self._dump(service, grep=grep)

        if not dump_grep:
            return False

        return dump_grep.strip().find(search) > -1