magic parser doesn't process dictionaries with spaces after ":"

[RafalSkolasinski]

When setting options via magic parser contains dictionary it fails to process whenever there is space after a colon. Please see following code.

Cell 1 (imports)

import numpy as np
import holoviews as hv
hv.notebook_extension()

Cell 2 (doesn't respect fontsize)

%%opts Image [fontsize={'ticks': 50}]
hv.Image(np.random.rand(10, 10))

Cell 3 (does respect fontsize)

%%opts Image [fontsize={'ticks':50}]
hv.Image(np.random.rand(10, 10))

---

Note:
when working locally with the notebook I got a warning message

WARNING:root:Warning: Ignoring keyword pair that fails to evaluate: 'fontsize={'ticks':,50}'

but when working via jupyterhub there is no warning.

[jlstevens]

Thanks for reporting this!

I believe this issue is related to #270.

[philippjfr]

Yes, this a duplicate of #270. Closing.