python: can i set a variable to equal a function of itself?

Question

Can I do this?

var1 = some_function(var1)

When I tried to do this I got errors, but perhaps I was doing something wrong.

Answer 1

If the variable has been previously defined, you can do that yes.

Example:

def f(x):
    return x+1

var1 = 5
var1 = f(var1)
# var1 is now 6

If the variable has not been defined previously, you can't do that, simply because there is no value that could be passed to the function.

Answer 2

def myfun(param):
    return param * 2

y = 4
y = myfun(y)
print (y)

Works fine. prints 8;

So you could describe better the problem you're experiencing, preferably with full error traceback and source code I can run to reproduce the problem.