Parse a YAML with duplicate anchors in Python

I'm just getting started with both YAML and Python and I'm trying to parse a YAML in Python which contains anchors and aliases.
In this YAML I overwrite the anchors to make certain nodes have different values.

An example of my YAML:

Some Colors: &some_colors
 color_primary: &color_primary "#112233FF"
 color_secondary: &color_secondary "#445566FF"

Element: &element
 color: *color_primary

Overwrite some colors: &overwrite_colors
 color_primary: &color_primary "#000000FF"

Another element: &another_element
 color: *color_primary

Which has the expected outcome of (in JSON):

{
    "Some Colors": {
        "color_primary": "#112233FF",
        "color_secondary": "#445566FF"
    },
    "Element": {
        "color": "#112233FF"
    },
    "Overwrite some colors": {
        "color_primary": "#000000FF"
    },
    "Another element": {
        "color": "#000000FF"
    }
}

I tested the above YAML snippet here

From what I've read in the YAML docs; this should've been possible from version 1.1 (I think), but at least YAML version 1.2 should support it.

But whenever I try to parse the YAML, using PyYAML (with yaml.load()) or the ruamel,yaml package (with ruamel.yaml.load()), I get the 'duplicate anchor' error.

What am I doing wrong here? And how to fix this?

EDIT:

With the help of ruamel's owner I've found a solution to the above question.

As of ruamel v0.12.3 the above works as expected, although you will receive ReusedAnchorWarnings.
These warnings can be suppressed with the following snippet:

import warnings
from ruamel.yaml.error import ReusedAnchorWarning

warnings.simplefilter("ignore", ReusedAnchorWarning)

Giving credits where this is due; all of them go to ruamel's owner.

As an added question; when I modify the above YAML to (notice the change at // <-- Added this):

Some Colors: &some_colors
 color_primary: &color_primary "#112233FF"
 color_secondary: &color_secondary "#445566FF"

Element: &element
 color: *color_primary

Overwrite some colors: &overwrite_colors
 <<: *some_colors   // <-- Added this to include 'color_secondary' as well
 color_primary: &color_primary "#000000FF"

Another element: &another_element
 color: *color_primary

The output is:

{
    "Some Colors": {
        "color_primary": "#000000FF",
        "color_secondary": "#445566FF"
    },
    "Element": {
        "color": "#112233FF"
    },
    "Overwrite some colors": {
        "color_primary": "#000000FF",
        "color_secondary": "#445566FF"
    },
    "Another element": {
        "color": "#445566FF" // <-- Now the value is 'color_secondary' instead of 'color_primary'?
    }
}

Why is the color of Another element looking at the value of color_secondary instead?

Is there any way to fix this as well?