Question

I have the following method definition in my class:

def show_values(self):
        for node in self.Nodes:
            nod = self.Nodes[node]
            print self.M.nod.value

I receive the following error

File "nfg.py", line 30, in show_values
    print self.M.nod.value
AttributeError: 'Model' object has no attribute 'nod'

I want to reach to self.M.(self.Nodes[node]).value, of course, but do not know
how. Can you help me?

Answer 1

Assuming self.Nodes[node] is a string that you want to use for an attribute lookup, try the following:

def show_values(self):
    for node in self.Nodes:
        nod = self.Nodes[node]
        print getattr(self.M, nod).value

Note that getattr(foo, 'bar') is equivalent to foo.bar.

If self.M is a dictionary or other mapping type and you want to do a key lookup, use the following:

def show_values(self):
    for node in self.Nodes:
        nod = self.Nodes[node]
        print self.M[nod].value