ICE allows one to create rigid bodies at at given rate. I would like to
do the same thing using Python.

The Application.FirstFrame() or Application.NextFrame() commands do move the animation but all
rigid bodies end up appearing at the first frame if one goes to the beginning of the animation.
A reference to appropriate command would be great.

To create rigid bodies within a Python script it is possible to do something like this.

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Application.FirstFrame()
NUMFLAKES = 10
for i in range(NUMFLAKES):
oflake = application.CreatePrim("Cube”,"MeshSurface")
oflake.SclX = 5
...
oflake.RotZ = -3
Application.NextFrame() # Moves playback control but rigid body appears at frame 1 in playback
Application.CreateActiveRigidBody(oflake)
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