在使用pymongo時遇到了乙個小坑：
在flask框架中，將字典插入mongodb後再返回就報錯
'***x'
)def
main()
:...
data =
mycol.insert_one(data)
return data
traceback (most recent call last):
response = self.handle_exception(e)
reraise(exc_type, exc_value, tb)
file "/home/xiang/.local/lib/python3.6/site-packages/flask/_compat.py", line 39, in reraise
raise value
response = self.full_dispatch_request()
return self.finalize_request(rv)
response = self.make_response(rv)
rv = jsonify(rv)
file "/home/xiang/.local/lib/python3.6/site-packages/flask/json/__init__.py", line 370, in jsonify
dumps(data, indent=indent, separators=separators) + "\n",
file "/home/xiang/.local/lib/python3.6/site-packages/flask/json/__init__.py", line 211, in dumps
rv = _json.dumps(obj, **kwargs)
file "/home/xiang/.local/lib/python3.6/site-packages/******json/__init__.py", line 412, in dumps
**kw).encode(obj)
file "/home/xiang/.local/lib/python3.6/site-packages/******json/encoder.py", line 298, in encode
chunks = list(chunks)
file "/home/xiang/.local/lib/python3.6/site-packages/******json/encoder.py", line 696, in _iterencode
for chunk in _iterencode_dict(o, _current_indent_level):
file "/home/xiang/.local/lib/python3.6/site-packages/******json/encoder.py", line 652, in _iterencode_dict
for chunk in chunks:
file "/home/xiang/.local/lib/python3.6/site-packages/******json/encoder.py", line 716, in _iterencode
o = _default(o)
file "/home/xiang/.local/lib/python3.6/site-packages/flask/json/__init__.py", line 100, in default
return _json.jsonencoder.default(self, o)
file "/home/xiang/.local/lib/python3.6/site-packages/******json/encoder.py", line 273, in default
o.__class__.__name__)
typeerror: object of type objectid is not json serializable
參考：
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