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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 required_header(header):
 """Function that verify if the header parameter is a essential header :param header: A string represented a header :returns: A boolean value that represent if the header is required """

    if header in IGNORE_HEADERS:
        return False

    if header.startswith('HTTP_') or header == 'CONTENT_TYPE':
        return True

    return False