feat(1070_convert-to-base-2): add py3 soln

1070_convert-to-base-2/python3/solution.py

@@ -0,0 +1,15 @@
+class Solution:
+    def baseNeg2(self, n: int) -> str:
+        result = ''
+        
+        while n != 0:
+            rem = n % -2
+            n = n // -2
+            
+            if rem < 0:
+                n += 1
+                rem += 2
+            
+            result = str(rem) + result
+        
+        return result if result != '' else '0'