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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def euclidean3d(v1, v2):
 """Faster implementation of euclidean distance for the 3D case."""

    if not len(v1) == 3 and len(v2) == 3:
        print("Vectors are not in 3D space. Returning None.")
        return None
    return np.sqrt((v1[0] - v2[0]) ** 2 + (v1[1] - v2[1]) ** 2 + (v1[2] - v2[2]) ** 2)