from dash import Dash, html, dcc, callback, Output, Input
import plotly.express as px
import pandas as pd


df = pd.read_csv(
    "https://raw.githubusercontent.com/plotly/datasets/master/gapminder_unfiltered.csv"
)


app = Dash()

# Requires Dash 2.17.0 or later
app.layout = [
    html.H1(children="Title of Dash App", style={"textAlign": "center"}),
    dcc.Dropdown(df.country.unique(), "Canada", id="dropdown-selection"),
    dcc.Graph(id="graph-content"),
]


@callback(Output("graph-content", "figure"), Input("dropdown-selection", "value"))
def update_graph(value):
    dff = df[df.country == value]
    return px.line(dff, x="year", y="pop")

#comments

if __name__ == "__main__":
    app.run(debug=True, host="0.0.0.0", port="7860")