Update app.py

app.py

@@ -61,13 +61,16 @@ def process_file(file):
     if "Shipping Province" in df.columns:
         output_df["Province/State"] = df["Shipping Province"]
 
-    # 6. ZipCode (pad 4-digit US zips with a leading zero)
+    # 6. ZipCode (pad 4-digit US zips with a leading zero + apostrophe for text)
     if "Shipping ZIP" in df.columns:
         zip_raw = df["Shipping ZIP"].astype(str).str.strip()
         mask_us = output_df["CountryCode"] == "US"
         mask_4  = zip_raw.str.len() == 4
-        zip_fixed = zip_raw.where(~(mask_us & mask_4), "0" + zip_raw)
-        output_df["ZipCode"] = zip_fixed
+        # pad to 5 digits
+        zip_padded = zip_raw.where(~(mask_us & mask_4), "0" + zip_raw)
+        # prefix apostrophe so Excel treats it as text and preserves leading zero
+        zip_final  = zip_padded.where(~(mask_us & mask_4), "'" + zip_padded)
+        output_df["ZipCode"] = zip_final
 
     # 7. CountryCode
     if "Shipping Country Code" in df.columns: