title: KeyError when using .format on a string in Python
body: <p>I have a string and I want to use <strong>.format</strong> function of python to add some variables in it on runtime, This is my string :</p>
  
  <pre><code>'{"auth": {"tenantName": "{Insert String Here}", "passwordCredentials": {"username": "{insert String here}", "password": "{insert String Here}"}}}'
  </code></pre>
  
  <p>when I use .format like this:</p>
  
  <pre><code>credentials='{"auth": {"tenantName": "{tenant}", "passwordCredentials": {"username": "{admin}", "password": "{password}"}}}'.format(tenant='me',admin='test',password='123')
  </code></pre>
  
  <p>It gives me the following error:</p>
  
  <pre><code>KeyError: '"auth"'
  </code></pre>
  
  <p>Any Help? Thanks in Advance.</p>