Add task7 files 7-main.py and 7-islower.py

Author: samuelselasi

0x01-python-if_else_loops_functions/7-islower.py

@@ -0,0 +1,6 @@
+#!/usr/bin/python3
+def islower(c):
+    if ord(c) >= 97 and ord(c) <= 122:
+        return True
+    else:
+        return False