def plot_vectors(vectors, colors):
    """
    Plots vectors on the xy-plane. The `vectors` parameter is a Python list.
    Each vector is specified in the format [start_x, start_y, end_x, end_y]
    """

    start_point_x = [vector[0] for vector in vectors]
    start_point_y = [vector[1] for vector in vectors]
    direction_x = [vector[2] - vector[0] for vector in vectors]
    direction_y = [vector[3] - vector[1] for vector in vectors]

    plt.quiver(start_point_x, start_point_y, direction_x, direction_y, scale_units="xy", angles="xy", scale=1, color=colors)