
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
The following propositions are given:

(1) If vectors $\overrightarrow{AB}$ and $\overrightarrow{CD}$ are collinear, then points $A$, $B$, $C$, and $D$ must lie on the same straight line;

(2) If $a$ and $b$ are both unit vectors, then $a=b$;

(3) The graph of the function $f(x)=4\sin(2x+\frac{\pi}{3})$ ($x\in\mathbb{R}$) is symmetric about the point $\left(-\frac{\pi}{6},0\right)$;

(4) Angles in the first or second quadrant can serve as interior angles of a triangle.

The correct proposition numbers are $\boxed{\text{(3)}}$.

Present the answer in LaTex format: \boxed{Your answer}
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