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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_raw_list_data(data, proxy_type='http', proxy_userpwd=None):
 """Iterate over proxy servers found in the raw data"""

    if not isinstance(data, six.text_type):
        data = data.decode('utf-8')
    for orig_line in data.splitlines():
        line = orig_line.strip().replace(' ', '')
        if line and not line.startswith('#'):
            try:
                host, port, username, password = parse_proxy_line(line)
            except InvalidProxyLine as ex:
                logger.error(ex)
            else:
                if username is None and proxy_userpwd is not None:
                    username, password = proxy_userpwd.split(':')
                yield Proxy(host, port, username, password, proxy_type)