<｜begin▁of▁sentence｜>### Instruction:
As a sales representative, imagine you are working with a company that sells graph visualization software to data scientists and engineers. A potential client, an academic research group, is exploring network analysis and visualization. They want to create a visualization of a simple tree graph with 7 vertices, where each vertex has 2 children, to represent a binary tree structure. They are specifically interested in using the LightToDarkEdgeDrawer in igraph to draw the edges in a way that indicates the direction with a light-to-dark style. Your task is to guide them on how to achieve this using the igraph library to meet their specific visualization needs.
### Response:
import igraph
from igraph.drawing import Plot
from igraph.drawing.edge import LightToDarkEdgeDrawer

# Creating a graph
g = igraph.Graph.Tree(7, 2)

# Setting up visual style
visual_style = {}
visual_style['vertex_size'] = 20
visual_style['edge_curved'] = False

# Creating a plot with a light-to-dark edge drawing style
plot = Plot('/path/to/tree.png', bbox=(300, 300), background='white')
ctx = plot.ctx
palette = igraph.drawing.colors.ClusterColoringPalette(20)
plot.add(g, **visual_style, edge_drawer=LightToDarkEdgeDrawer(ctx, palette))
plot.redraw()
plot.save()
<|EOT|>
