+
+
+def _match_one(filter_part, dct):
+    COMPARISON_OPERATORS = {
+        '<': operator.lt,
+        '<=': operator.le,
+        '>': operator.gt,
+        '>=': operator.ge,
+        '=': operator.eq,
+        '!=': operator.ne,
+    }
+    operator_rex = re.compile(r'''(?x)\s*
+        (?P<key>[a-z_]+)
+        \s*(?P<op>%s)(?P<none_inclusive>\s*\?)?\s*
+        (?:
+            (?P<intval>[0-9.]+(?:[kKmMgGtTpPeEzZyY]i?[Bb]?)?)|
+            (?P<strval>(?![0-9.])[a-z0-9A-Z]*)
+        )
+        \s*$
+        ''' % '|'.join(map(re.escape, COMPARISON_OPERATORS.keys())))
+    m = operator_rex.search(filter_part)
+    if m:
+        op = COMPARISON_OPERATORS[m.group('op')]
+        if m.group('strval') is not None:
+            if m.group('op') not in ('=', '!='):
+                raise ValueError(
+                    'Operator %s does not support string values!' % m.group('op'))
+            comparison_value = m.group('strval')
+        else:
+            try:
+                comparison_value = int(m.group('intval'))
+            except ValueError:
+                comparison_value = parse_filesize(m.group('intval'))
+                if comparison_value is None:
+                    comparison_value = parse_filesize(m.group('intval') + 'B')
+                if comparison_value is None:
+                    raise ValueError(
+                        'Invalid integer value %r in filter part %r' % (
+                            m.group('intval'), filter_part))
+        actual_value = dct.get(m.group('key'))
+        if actual_value is None:
+            return m.group('none_inclusive')
+        return op(actual_value, comparison_value)
+
+    UNARY_OPERATORS = {
+        '': lambda v: v is not None,
+        '!': lambda v: v is None,
+    }
+    operator_rex = re.compile(r'''(?x)\s*
+        (?P<op>%s)\s*(?P<key>[a-z_]+)
+        \s*$
+        ''' % '|'.join(map(re.escape, UNARY_OPERATORS.keys())))
+    m = operator_rex.search(filter_part)
+    if m:
+        op = UNARY_OPERATORS[m.group('op')]
+        actual_value = dct.get(m.group('key'))
+        return op(actual_value)
+
+    raise ValueError('Invalid filter part %r' % filter_part)
+
+
+def match_str(filter_str, dct):
+    """ Filter a dictionary with a simple string syntax. Returns True (=passes filter) or false """
+
+    return all(
+        _match_one(filter_part, dct) for filter_part in filter_str.split('&'))
+
+
+def match_filter_func(filter_str):
+    def _match_func(info_dict):
+        if match_str(filter_str, info_dict):
+            return None
+        else:
+            video_title = info_dict.get('title', info_dict.get('id', 'video'))
+            return '%s does not pass filter %s, skipping ..' % (video_title, filter_str)
+    return _match_func
+
+
+def parse_dfxp_time_expr(time_expr):
+    if not time_expr:
+        return 0.0
+
+    mobj = re.match(r'^(?P<time_offset>\d+(?:\.\d+)?)s?$', time_expr)
+    if mobj:
+        return float(mobj.group('time_offset'))
+
+    mobj = re.match(r'^(\d+):(\d\d):(\d\d(?:\.\d+)?)$', time_expr)
+    if mobj:
+        return 3600 * int(mobj.group(1)) + 60 * int(mobj.group(2)) + float(mobj.group(3))
+
+
+def srt_subtitles_timecode(seconds):
+    return '%02d:%02d:%02d,%03d' % (seconds / 3600, (seconds % 3600) / 60, seconds % 60, (seconds % 1) * 1000)
+
+
+def dfxp2srt(dfxp_data):
+    _x = functools.partial(xpath_with_ns, ns_map={'ttml': 'http://www.w3.org/ns/ttml'})
+
+    def parse_node(node):
+        str_or_empty = functools.partial(str_or_none, default='')
+
+        out = str_or_empty(node.text)
+
+        for child in node:
+            if child.tag in (_x('ttml:br'), 'br'):
+                out += '\n' + str_or_empty(child.tail)
+            elif child.tag in (_x('ttml:span'), 'span'):
+                out += str_or_empty(parse_node(child))
+            else:
+                out += str_or_empty(xml.etree.ElementTree.tostring(child))
+
+        return out
+
+    dfxp = xml.etree.ElementTree.fromstring(dfxp_data.encode('utf-8'))
+    out = []
+    paras = dfxp.findall(_x('.//ttml:p')) or dfxp.findall('.//p')
+
+    if not paras:
+        raise ValueError('Invalid dfxp/TTML subtitle')
+
+    for para, index in zip(paras, itertools.count(1)):
+        begin_time = parse_dfxp_time_expr(para.attrib['begin'])
+        end_time = parse_dfxp_time_expr(para.attrib.get('end'))
+        if not end_time:
+            end_time = begin_time + parse_dfxp_time_expr(para.attrib['dur'])
+        out.append('%d\n%s --> %s\n%s\n\n' % (
+            index,
+            srt_subtitles_timecode(begin_time),
+            srt_subtitles_timecode(end_time),
+            parse_node(para)))
+
+    return ''.join(out)
+
+
+class PerRequestProxyHandler(compat_urllib_request.ProxyHandler):
+    def __init__(self, proxies=None):
+        # Set default handlers
+        for type in ('http', 'https'):
+            setattr(self, '%s_open' % type,
+                    lambda r, proxy='__noproxy__', type=type, meth=self.proxy_open:
+                        meth(r, proxy, type))
+        return compat_urllib_request.ProxyHandler.__init__(self, proxies)
+
+    def proxy_open(self, req, proxy, type):
+        req_proxy = req.headers.get('Ytdl-request-proxy')
+        if req_proxy is not None:
+            proxy = req_proxy
+            del req.headers['Ytdl-request-proxy']
+
+        if proxy == '__noproxy__':
+            return None  # No Proxy
+        return compat_urllib_request.ProxyHandler.proxy_open(
+            self, req, proxy, type)