title: f-string in yaxis.set_major_formatter
body: <p>I have the following code:</p>
  <pre><code>import pandas as pd
  from pandas import DataFrame as df
  import matplotlib
  from pandas_datareader import data as web
  import matplotlib.pyplot as plt
  import datetime
  import yfinance as yf
  import matplotlib.ticker as mtick
  from matplotlib.ticker import (MultipleLocator, FormatStrFormatter,
                                 AutoMinorLocator)
  import currency
  import warnings
  
  warnings.filterwarnings(&quot;ignore&quot;)
  
  start = datetime.date(2000,1,1)
  end = datetime.date.today()
  
  
  stock =  'goog'
  fig, ax = plt.subplots(dpi=300, figsize =(8,4) )
  data = web.DataReader(stock, 'yahoo', start, end)
  data['Close'].plot()
  ax.tick_params(axis='y', colors='midnightblue')
  
  ax.tick_params(axis='x', colors=&quot;k&quot;)
  pg = yf.Ticker(stock)
  # sn = pg.info['shoName']
  sn = pg.info['shortName']
  
  b = pg.info['currency']
  c = currency.symbol(f&quot;{b}&quot;)
  ax.set_ylabel(f&quot;Price ({pg.info['currency']})&quot;)
  ax.xaxis.grid(False, which='minor')
  ax.yaxis.set_major_formatter('${x:1.2f}')
  ax.margins(x=0)
  # plt.savefig(f&quot;{sn} {end.strftime('%d - %b%Y')}&quot;, bbox_inches='tight', dpi = 500)
  print(sn)
  print('datetime date =', start)
  plt.show()
  print()
  </code></pre>
  <p>The issue i am facing is <code>ax.yaxis.set_major_formatter('${x:1.2f}')</code>. I need to get a f-string to evaluate <code>c</code>. This would give the currency of any country instead of using $ sign. However it does not seem to evaluate f-string, could you please advise any possible alternatives?</p>