REST API : Expecting property name enclosed in double quotes

Traceback (most recent call last):
File “/home/frappe/frappe-bench/apps/frappe/frappe/app.py”, line 66, in application
response = frappe.api.handle()
File “/home/frappe/frappe-bench/apps/frappe/frappe/api.py”, line 117, in handle
data = json.loads(frappe.local.form_dict.data)
File “/usr/lib/python2.7/json/init.py”, line 339, in loads
return _default_decoder.decode(s)
File “/usr/lib/python2.7/json/decoder.py”, line 364, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
File “/usr/lib/python2.7/json/decoder.py”, line 380, in raw_decode
obj, end = self.scan_once(s, idx)
ValueError: Expecting property name enclosed in double quotes: line 1 column 2 (char 1)

getting this on api POST. Below is data
{“item_code”: “001”, “item_group”: “xyz”, “default_uom”: “kg”, “is_stock_item”: 1}

Solved using
{“item_code”: “001”, “item_group”: “xyz”, “default_uom”:" kg", “is_stock_item”: 1}