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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 realtime(widget, url_name=None, url_regex=None, time_interval=None):
 """ Return a widget as real-time. Args: widget (Widget):
 the widget to register and return as real-time. url_name (str):
 the URL name to call to get updated content. url_regex (regex):
 the URL regex to be matched. time_interval (int):
 the interval of refreshment in milliseconds. Returns: Widget: the "real-timed" widget. """

    if not hasattr(widget, 'get_updated_content'):
        raise AttributeError('Widget %s must implement get_updated_content '
                             'method.' % widget)
    elif not callable(widget.get_updated_content):
        raise ValueError('get_updated_content in widget %s is not callable'
                         % widget)

    if url_name is None:
        if getattr(widget, 'url_name', None) is not None:
            url_name = widget.url_name
        else:
            url_name = widget.__class__.__name__

    if url_name in [w.url_name for w in REALTIME_WIDGETS]:
        raise ValueError('URL name %s is already used by another '
                         'real time widget.' % url_name)

    if url_regex is None:
        if getattr(widget, 'url_regex', None) is not None:
            url_regex = widget.url_regex
        else:
            url_regex = sha256(url_name.encode('utf-8'))
            url_regex = url_regex.hexdigest()[:32]
            url_regex = 'realtime/' + url_regex

    if url_regex in [w.url_regex for w in REALTIME_WIDGETS]:
        raise ValueError('URL regex %s is already used by another '
                         'real time widget.' % url_regex)

    if time_interval is None:
        if getattr(widget, 'time_interval', None) is not None:
            time_interval = widget.time_interval
        else:
            time_interval = app_settings.default_time_interval

    from django.views.generic import View
    from braces.views import AjaxResponseMixin, JSONResponseMixin

    # pylama:ignore=C0111,R0201
    class PartialResponse(JSONResponseMixin, AjaxResponseMixin, View):
        def get_data(self):
            return widget.get_updated_content()

        def get(self, request, *args, **kwargs):
            return self.get_ajax(request, *args, **kwargs)

        def get_ajax(self, request, *args, **kwargs):
            return self.render_json_response(self.get_data())

    PartialResponse.url_name = url_name
    PartialResponse.url_regex = url_regex
    PartialResponse.time_interval = time_interval

    REALTIME_WIDGETS.append(PartialResponse)

    if not hasattr(widget, 'url_name'):
        widget.url_name = url_name
    if not hasattr(widget, 'url_regex'):
        widget.url_regex = url_regex
    if not hasattr(widget, 'time_interval'):
        widget.time_interval = time_interval

    return widget