most commands moved into cogs

lib.py

@@ -1,7 +1,9 @@
 import json
 import logging
 import sqlite3
-from os import walk, listdir
+from os import walk, listdir, path
+
+DEFAULT_PREFIX = "$"  # The prefix you want everyone to have if you don't define your own
 
 
 class DB:
@@ -87,6 +89,13 @@ class CogsPrepare:
 
 
 class Commands:
+    @staticmethod
+    def chech_json():
+        if not path.isfile('prefix.json'):
+            with open('prefix.json', 'w+') as f:
+                f.write("")
+            f.close()
+
     @staticmethod
     async def set_prefix(ctx, prefix: str):
         await Commands.write_json(ctx.guild.id, "prefix", prefix)
@@ -142,3 +151,20 @@ class Commands:
         with open('prefix.json', 'w') as _f:
             json.dump(_json, _f, indent=4)
             _f.close()
+
+    @staticmethod
+    def determine_prefix(bot, msg):
+        guild = msg.guild
+        with open('prefix.json', 'r', encoding='utf-8') as fp:  # Open the JSON
+            parameter = DEFAULT_PREFIX
+            try:
+                _json = json.load(fp)  # Load the custom prefixes
+            except error:
+                _json = {}
+        if guild:  # If the guild exists
+            try:
+                parameter = _json[f"{guild.id}"]["prefix"]  # Read prefix from json if is setted up
+            except error:
+                pass
+        return parameter
+