title: I got: chart_studio.exceptions.PlotlyRequestError: Authentication credentials were not provided
body: <p>I am working locally(in my pc) just testing and learning PLOTLY  3.7.5.
  with anaconda env active.
  The code example is given by plotly</p>
  
  <p>Code:</p>
  
  <pre><code>import plotly.plotly as py  # Here all begins (Look)
  # import chart_studio.plotly as py  # inted of the line bellow (optional to  try)
  import plotly.graph_objs as go
  import pandas as pd
  from datetime import datetime
  
  if __name__ == '__main__':
      df = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/finance-charts-apple.csv')
      trace = go.Ohlc(x=df['Date'],
                      open=df['AAPL.Open'],
                      high=df['AAPL.High'],
                      low=df['AAPL.Low'],
                      close=df['AAPL.Close'])
      data = [trace]
      py.iplot(data, filename='simple_ohlc')
  </code></pre>
  
  <p>note  (Look): I got the warning error:</p>
  
  <blockquote>
    <p><em>'please install the chart-studio package and use the chart_studio.plotly module instead.'</em></p>
  </blockquote>