DeprecationWarning in traitlets

[hiamandeep]

executing this in Jupyter notebook,

class MyWidget(widgets.DOMWidget):
    _view_name = Unicode('MyView', sync=True)
    value = Unicode(input_form+javascript, sync=True)

gives warning:

home/aman/mylatex/lib/python2.7/site-packages/ipykernel/main.py:2: DeprecationWarning: metadata {'sync': True} was set from the constructor. Metadata should be set using the .tag() method, e.g., Int().tag(key1='value1', key2='value2')
from ipykernel import kernelapp as app
/home/aman/mylatex/lib/python2.7/site-packages/ipykernel/main.py:3: DeprecationWarning: metadata {'sync': True} was set from the constructor. Metadata should be set using the .tag() method, e.g., Int().tag(key1='value1', key2='value2')
app.launch_new_instance()

Can't figure out how to solve this.

[SylvainCorlay]

Instead of passing sync=True as a keyword argument, use the tag function.

_view_name = Unicode('MyView').tag (sync=True) 

[hiamandeep]

Thanks!