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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 url_scan(self, url, opts, functionality, enabled_functionality, hide_progressbar):
 """ This is the main function called whenever a URL needs to be scanned. This is called when a user specifies an individual CMS, or after CMS identification has taken place. This function is called for individual hosts specified by `-u` or for individual lines specified by `-U`. @param url: this parameter can either be a URL or a (url, host_header) tuple. The url, if a string, can be in the format of url + " " + host_header. @param opts: options object as returned by self._options(). @param functionality: as returned by self._general_init. @param enabled_functionality: as returned by self._general_init. @param hide_progressbar: whether to hide the progressbar. @return: results dictionary. """

        self.out.debug('base_plugin_internal.url_scan -> %s' % str(url))
        if isinstance(url, tuple):
            url, host_header = url
        else:
            url, host_header = self._process_host_line(url)

        url = common.repair_url(url)
        if opts['follow_redirects']:
            url, host_header = self.determine_redirect(url, host_header, opts)

        need_sm = opts['enumerate'] in ['a', 'p', 't']
        if need_sm and (self.can_enumerate_plugins or self.can_enumerate_themes):
            scanning_method = opts['method']
            if not scanning_method:
                scanning_method = self.determine_scanning_method(url,
                        opts['verb'], opts['timeout'], self._generate_headers(host_header))

        else:
            scanning_method = None

        enumerating_all = opts['enumerate'] == 'a'
        result = {}
        for enumerate in enabled_functionality:
            enum = functionality[enumerate]

            if common.shutdown:
                continue

            # Get the arguments for the function.
            kwargs = dict(enum['kwargs'])
            kwargs['url'] = url
            kwargs['hide_progressbar'] = hide_progressbar
            if enumerate in ['themes', 'plugins']:
                kwargs['scanning_method'] = scanning_method

            kwargs['headers'] = self._generate_headers(host_header)

            # Call to the respective functions occurs here.
            finds, is_empty = enum['func'](**kwargs)

            result[enumerate] = {'finds': finds, 'is_empty': is_empty}

        return result