[mod] tokyotoshokan dependecy to other engine removed

searx/engines/tokyotoshokan.py

 from lxml import html
 from searx.engines.xpath import extract_text
 from datetime import datetime
-from searx.engines.nyaa import int_or_zero, get_filesize_mul
 from searx.url_utils import urlencode
+from searx.utils import get_torrent_size
 
 # engine dependent config
 categories = ['files', 'videos', 'music']
 search_url = base_url + 'search.php?{query}'
 
 
+# convert a variable to integer or return 0 if it's not a number
+def int_or_zero(num):
+    if isinstance(num, list):
+        if len(num) < 1:
+            return 0
+        num = num[0]
+    if num.isdigit():
+        return int(num)
+    return 0
+
+
 # do search-request
 def request(query, params):
     query = urlencode({'page': params['pageno'], 'terms': query})
                 try:
                     # ('1.228', 'GB')
                     groups = size_re.match(item).groups()
-                    multiplier = get_filesize_mul(groups[1])
-                    params['filesize'] = int(multiplier * float(groups[0]))
+                    params['filesize'] = get_torrent_size(groups[0], groups[1])
                 except:
                     pass
             elif item.startswith('Date:'):