Networkx not giving correct colors based on wegiths from data frame

Question

I am trying to create graphs of conflicts and alliances between drug trafficking organizations. I want conflicts to be graphed as red edges, and alliances to be graphed as blue edges. I gave each relationship a weight so that Networkx could give each relationship a different color. This is the edgelist I have:

But the colors shown are inconsistent with the weights. I have tried different things but nothing seems to work. This is my code:

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import networkx as nx
import pandas as pd
import matplotlib.pyplot as plt
import numpy as np

df=pd.read_csv("2004N.csv")
df

    Source  Target  Weight
0   Gulf Cartel     Sinaloa Cartel  -1
1   Tijuana Cartel  Sinaloa Cartel  -1
2   Gulf Cartel     Juarez Cartel   1
3   Tijuana Cartel  Gulf Cartel     1
4   Tijuana Cartel  Juarez Cartel   1
5   Juarez Cartel   Sinaloa Cartel  -1

 

G=nx.from_pandas_edgelist(df, 'Source', 'Target', edge_attr="Weight")

plt.figure(1,figsize=(12,8))

nx.draw(G, with_labels=True, node_color='skyblue', node_size=1500, edge_color=df['Weight'], width=5.0)

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This is the image I get:

Color of edges are not consistent with weights

Any help will be very much appreciated.