temp22.sobj is not UTF-8 encoded

edit

Please provide a reproducible example. Here, we don't have G to try your code.

I am trying to do something alike. This is of course a hazard guess. For me

sage: P = graphs.PetersenGraph().to_directed()
sage: V = P.vertices()
sage: V[5] = 'fünf'
sage: V
[0, 1, 2, 3, 4, 'f\xc3\xbcnf', 6, 7, 8, 9]
sage: W = [ (V[k], V[n], '%s%s'%(V[k],V[n])) for k, n, nonelabel in P.edges() ]
sage: G = DiGraph( [V, W], format='vertices_and_edges' )
sage: save( G.all_simple_cycles(), 'temp22' )

produces the file,

-rw-rw-r--  1 dan dan   745 Apr  7 15:05 temp22.sobj

and then

sage: G_reloaded = load( r'/home/dan/temp22' )
sage: G_reloaded == G.all_simple_cycles()
True

This is an old linux machine running

sage: version()
'SageMath version 7.5.1, Release Date: 2017-01-15'

Please try to describe in a similar way the problem.

Okay just do A=Matrix([[0,1],[1,0]]) G=Digraph(A)
I'm not sure what save does or where it get's saved to

Please edit your question to provide a complete reproducible example.

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For instance, typing

If we define `f` by

    def f(x, y):
        return (x, y)

then `f(2, 3)` returns `(2, 3)` but `f(2)` gives:

    TypeError: f() takes exactly 2 arguments (1 given)

produces:

If we define f by

def f(x, y):
    return (x, y)

then f(2, 3) returns (2, 3) but f(2) gives:

TypeError: f() takes exactly 2 arguments (1 given)

Please edit your question to do that.