switched currency convert to duckduckgo and added Bitcoin to currency list

searx/data/currencies.json

         ], 
         "scellino keniota": [
             "KES"
-        ]
+        ],
+	"bitcoin": [
+		"XBT"
+	]	
     }, 
     "iso4217": {
+	"XBT":{
+	    "fr": "Bitcoin", 
+            "en": "Bitcoin", 
+            "nl": "Bitcoin", 
+            "de": "Bitcoin", 
+            "it": "Bitcoin", 
+            "hu": "Bitcoin", 
+            "es": "Bitcoin"
+	},	
         "DZD": {
             "fr": "Dinar alg\u00e9rien", 
             "en": "Algerian dinar", 
             "es": "Libra sudanesa"
         }
     }
-}
+}

searx/engines/currency_convert.py

     unicode = str
 
 categories = []
-url = 'https://finance.google.com/finance/converter?a=1&from={0}&to={1}'
+url = 'https://duckduckgo.com/js/spice/currency/1/{0}/{1}'
 weight = 100
 
 parser_re = re.compile(b'.*?(\\d+(?:\\.\\d+)?) ([^.0-9]+) (?:in|to) ([^.0-9]+)', re.I)
 
 
 def response(resp):
+    """remove first and last lines to get only json"""
+    json_resp = resp.text[resp.text.find('\n')+1:resp.text.rfind('\n')-2]
     results = []
-    pat = '<span class=bld>(.+) {0}</span>'.format(
-        resp.search_params['to'].upper())
-
     try:
-        conversion_rate = re.findall(pat, resp.text)[0]
-        conversion_rate = float(conversion_rate)
+        conversion_rate = float(json.loads(json_resp)['conversion']['converted-amount'])
     except:
         return results
-
     answer = '{0} {1} = {2} {3}, 1 {1} ({5}) = {4} {3} ({6})'.format(
         resp.search_params['amount'],
         resp.search_params['from'],
         resp.search_params['to_name'],
     )
 
-    url = 'https://finance.google.com/finance?q={0}{1}'.format(
+    url = 'https://duckduckgo.com/js/spice/currency/1/{0}/{1}'.format(
         resp.search_params['from'].upper(), resp.search_params['to'])
 
     results.append({'answer': answer, 'url': url})