With PM. Model () as md:
A=PM. Normal (" a ", mu=1, sd=5)

C=gamma (a)
Print (c)

Traceback (the most recent call last) :
The File "D:/py/lab/jupyter/test. Py", line 17, in & lt; module>
C=gamma (a)
TypeError: ufunc 'gamma' not supported for the input types, and the inputs could not be safely coerced to any supported types "according to the casting rule 'safe'

, help some directions, thank you all for the first,