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Some functions in Sage or NumPy do not support symbolic arguments.

Plotting using such functions requires using them as callable functions.

The reference manual should insist on that...

(Currently, most if not all examples in the documentation use symbolic expressions.)

Here we use the NumPy functions in the question:

sage: import numpy as np

sage: parametric_plot([lambda u: u, np.sin], (0, pi))
Launched png viewer for Graphics object consisting of 1 graphics primitive

sage: parametric_plot([lambda u: u, np.cbrt], (0, pi))
Launched png viewer for Graphics object consisting of 1 graphics primitive

Here we use equivalent functions provided by SageMath:

sage: parametric_plot([lambda u: u, sin], (0, pi))
Launched png viewer for Graphics object consisting of 1 graphics primitive

sage: parametric_plot([lambda u: u, lambda u: real_nth_root(u, 3)], (0, pi))
Launched png viewer for Graphics object consisting of 1 graphics primitive