code:

### This code renders a scatter plot using a callback loading data first from a dataframe then, after a button is pressed, from an API. 

# Your imports and stuff
import dash
import dash_html_components as html
import dash_core_components as dcc
import pandas as pd
import plotly.express as px
import requests

external_stylesheets = ['https://codepen.io/chriddyp/pen/bWLwgP.css']

app = dash.Dash(__name__, external_stylesheets=external_stylesheets)

### Higher up you have a graph with some ID and a button
app.layout = html.Div([
    html.Button('Submit', id='btn-id-name', n_clicks=0),
    dcc.Graph(figure=None, id="graph-figure") 
    # IDK if you can actually make this None or if it needs some init.
    # Either way in the callback I say to get it some init data if the button hasn't been pressed yet.
])


# Down lower youll have your callback.
@app.callback(Output('graph-figure', 'figure'),
              [Input('btn-id-name', 'n_clicks')])
def some_func_name(n_clicks):
    if n_clicks: # If you've clicked the button. 
        headers = {
            "Content-Type": "application/json",
        }
        response = requests.get(
            f'https://api.dickbutt.com/api/v1/?param=bad_posting',
            auth="ABC123", headers=headers)

        # Do some stuff to the response here, make your fig
        new_fig = px.scatter(
            pd.DataFrame(response.json()),
            x="sepal_width",
            y="sepal_length"
        )
        return new_fig
    else: # If you have NOT clicked the button. 
        # Read in some initial data set if you want some starter thing. All callbacks are executed at runtime.
        df = pd.read_csv("init_data.csv")
        # Make some initial figure
        fig = px.scatter(df, x="sepal_width", y="sepal_length")
        return fig
    

if __name__ == '__main__':
    app.run_server(debug=True)