always() and f_always()

[jengelbertt]

Please write an example of the use of always() and f_always(). I am completely confused.
Are these two methods available via Mobject?

[JasonGrace2282]

always is supposed to be used like

d = Dot()
sq = Square()
always(d.next_to, sq, UP)

f_always is supposed to be used like

def calc_pos():
    sq.get_center()
sq = Square()
d = Dot()
f_always(d.move_to, calc_pos)

Admittedly, this is not very intuitive, so #3852 was introduced to make the syntax for always more like

d = Dot()
d.always.next_to(sq, UP)

Hopefully, if the devs can find the time, it will be included in Manim v0.19.0