lpython.py: Fix unsigned cast for CPython

Author: ubaidsk

src/runtime/lpython/lpython.py

@@ -17,14 +17,9 @@
 class UnsignedInteger:
     def __init__(self, bit_width, value):
         if isinstance(value, UnsignedInteger):
-            if bit_width != value.bit_width:
-                raise ValueError(f"Bit width mismatch: {bit_width} vs {value.bit_width}")
             value = value.value
-
-        if not (0 <= value < 2**bit_width):
-            raise ValueError(f"Value should be in range 0 to {2**bit_width-1} for a {bit_width}-bit unsigned integer.")
         self.bit_width = bit_width
-        self.value = value
+        self.value = value % (2**bit_width)
 
     def __bool__(self):
         return self.value != 0