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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 _get_trusted_comma(self, trusted, value):
 """Get the real value from a comma-separated header based on the configured number of trusted proxies. :param trusted: Number of values to trust in the header. :param value: Header value to parse. :return: The real value, or ``None`` if there are fewer values than the number of trusted proxies. .. versionadded:: 0.15 """

        if not (trusted and value):
            return
        values = [x.strip() for x in value.split(",")]
        if len(values) >= trusted:
            return values[-trusted]