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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_headers(lines, offset=0):
 """ Parse the headers in a STOMP response :param list(str) lines: the lines received in the message response :param int offset: the starting line number :rtype: dict(str,str) """

    headers = {}
    for header_line in lines[offset:]:
        header_match = HEADER_LINE_RE.match(header_line)
        if header_match:
            key = header_match.group('key')
            key = re.sub(r'\\.', _unescape_header, key)
            if key not in headers:
                value = header_match.group('value')
                value = re.sub(r'\\.', _unescape_header, value)
                headers[key] = value
    return headers