How to get name of a shader node group in Python (and check if there is a certain shader node inside it)

Question

The material is looking like this:

I'm trying with this code:

nodes = mat.node_tree.nodes
for n in mat.node_tree.nodes:
    print(m.name)
    #I use startswith so I can check if there are node groups duplicated
    if nodes.name.startswith("Custom Node"):
          #Here I want to dive inside the node group and check if there is an image texture node inside

And this is what I get in the console: Material Output Principled BSDF Group

I'm wondering how can I get the actual name of the group.

Then I would like to dive inside the node groups (all the node groups whose name start with "Custom Node" actually) and check if a certain node is inside them, let's say for example an image texture node. The code should be something like this

mat = bpy.data.materials.get(bpy.context.selected_objects[0].active_material.name)
mat.use_nodes = True
nodes = mat.node_tree.nodes
for n in mat.node_tree.nodes:
    print(n.name)
    #I use startsswith so I can check if there are node groups duplicated
    if n.name.startswith("Custom Node"):
        #Here I want to dive inside the node group and check if there is an image texture node inside. 
        #This DOESN'T WORK but helps to have an idea of what i want
        for n2 in n.node_tree.nodes:
            if n2.name == "ShaderNodeTexImage":
                print("Found Image texture")

Answer 1

So, a few things...

startwith should be startswith

To get the actual name of the group you need to check its label
if n.label.startswith("Custom Node"):

To compare you need to use ==
A single = is used to assign values.

To check for a particular node inside your group, use the following:

mat = bpy.data.materials.get(bpy.context.selected_objects[0].active_material.name)
mat.use_nodes = True
nodes = mat.node_tree.nodes
for n in nodes:
    if n.label.startswith("Custom Node"):
        for n2 in n.node_tree.nodes.values():
            if n2.name == "Image Texture":
                print (n2.name)
                print("Found Image texture")