JS1153: Cannot define get_Item or set_Item on an Expando class
Cannot define get_Item or set_Item on an Expando class. Methods reserved for the expando fields.
A member of an expando class is named get_Item or set_Item. This is not allowed because it leads to a conflict with the get_Item or set_Item properties that are implicitly defined for expando classes.
To correct this error
- Rename the class member named get_Item or set_Item.