diff --git a/opt_einsum/parser.py b/opt_einsum/parser.py
index 5c6ac53..d24e9be 100644
--- a/opt_einsum/parser.py
+++ b/opt_einsum/parser.py
@@ -309,7 +309,7 @@ def parse_einsum_input(operands: Any, shapes: bool = False) -> Tuple[str, str, L
     else:
         subscripts, operands = convert_interleaved_input(operands)
 
-   if shapes:
+    if shapes:
         operand_shapes = [list(s) for s in operands]
     else:
         operand_shapes = [o.shape for o in operands]