class - Python: typecasting a variable in an object method declaration? -


i'm new python, , have class such following:

class myclass:     var1 = 0     var2 = 1     var3 = 2     def function(self, x):         x.method(...yadda...)

for class, x object containing data , methods, , i'd able call methods within instance of myclass. there way specify x here object of type? instance, regularly 1 use following define object (from imported file called classfile):

newobj = classfile.myclass()

for object x in code above, can require of specific object type, built-in object or 1 define? how specify this?

i want code throw error or bypass object sent in not of desired type, preferably before start attempting call methods in (i.e. x.method()).

a better practice "implement" duck typing. in case 

def function(self, x):     try:         x.method(... yada ...)     except attributeerror:         raise myapierror

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