Hexagon $ ABCDEF, $ as pictured [in the attachment], is such that $ ABDE $ is a square with side length 20, $ \overline{AB}, \overline{CF} $, and $ \overline{DE} $ are all parallel, and $ BC = CD = EF = FA = 23 $. What is the largest integer not exceeding the length of $ \overline{CF} $?

$\textbf{(A) } 41 \qquad \textbf{(B) } 42 \qquad \textbf{(C) } 62 \qquad \textbf{(D) } 81 \qquad \textbf{(E) } \text{none of the above}$
1. **Identify the given information and the structure of the hexagon:**
   - Hexagon \( ABCDEF \) has \( ABDE \) as a square with side length 20.
   - \( \overline{AB}, \overline{CF}, \) and \( \overline{DE} \) are all parallel.
   - \( BC = CD = EF = FA = 23 \).

2. **Determine the coordinates of the vertices:**
   - Place the square \( ABDE \) on the coordinate plane with \( A(0, 0) \), \( B(20, 0) \), \( D(20, 20) \), and \( E(0, 20) \).

3. **Find the coordinates of points \( C \) and \( F \):**
   - Since \( BC = 23 \) and \( B(20, 0) \), point \( C \) must be 23 units away from \( B \) along the line parallel to \( \overline{DE} \). Therefore, \( C(20, -23) \).
   - Similarly, since \( EF = 23 \) and \( E(0, 20) \), point \( F \) must be 23 units away from \( E \) along the line parallel to \( \overline{AB} \). Therefore, \( F(0, -3) \).

4. **Calculate the length of \( \overline{CF} \):**
   - Use the distance formula to find \( \overline{CF} \):
     \[
     CF = \sqrt{(20 - 0)^2 + (-23 - (-3))^2} = \sqrt{20^2 + (-20)^2} = \sqrt{400 + 400} = \sqrt{800} = 20\sqrt{2}
     \]

5. **Determine the largest integer not exceeding \( 20\sqrt{2} \):**
   - Since \( \sqrt{2} \approx 1.414 \), we have:
     \[
     20\sqrt{2} \approx 20 \times 1.414 = 28.28
     \]
   - The largest integer not exceeding 28.28 is 28.

The final answer is \(\boxed{28}\)