so-example-debt-held-public-amt-multi-func-formatter.py

import requests
import pandas as pd
import matplotlib.pyplot as plt
import matplotlib.ticker as mtick
# ----------------------------------------------------------------------
page_size = 10000

url = 'https://api.fiscaldata.treasury.gov/services/api/fiscal_service/v2/accounting/od/debt_to_penny'

url_params = f'?page[size]={page_size}'

response = requests.get(url + url_params)

result_json = response.json()
# ----------------------------------------------------------------------

df = pd.DataFrame(result_json['data'])

df['record_date'] = pd.to_datetime(df['record_date'])

# ----------------------------------------------------------------------
plt.ion()
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df['debt_held_public_amt'] = pd.to_numeric(df['debt_held_public_amt'], errors='coerce')
df['intragov_hold_amt']    = pd.to_numeric(df['intragov_hold_amt'   ], errors='coerce')
df['tot_pub_debt_out_amt'] = pd.to_numeric(df['tot_pub_debt_out_amt'])

plt.ion()

ax = df.plot(x='record_date', y=['debt_held_public_amt', 'intragov_hold_amt', 'tot_pub_debt_out_amt'], kind='line', rot=90)

ax.yaxis.set_major_formatter(mtick.FuncFormatter(lambda x, pos: '$' + '{:1.0f}'.format(x/1000/1000/1000/1000) + 'T'))
# ----------------------------------------------------------------------