title: JSON generated manually works, but created through json.dumps does not work even if output seems to be exactly same
body: <p>I am using the <code>Marketo</code> API through the Python Library <a href="https://github.com/jepcastelein/marketo-rest-python" rel="nofollow noreferrer">marketo-rest-python</a>. I can create Leads and also Update them through the following basic code:</p>
  
  <pre><code>leads = [{"email":"joe@example.com","firstName":"Joe"},{"email":"jill@example.com","firstName":"Jill"}]
  lead = mc.execute(method='create_update_leads', leads=leads, action='createOnly', lookupField='email', 
                  asyncProcessing='false', partitionName='Default')
  </code></pre>
  
  <p>When i create programmatically this "leads" JSON object via</p>
  
  <pre><code>leads = []
  
  lead = {}
  lead['email'] = "joe@example.com"
  lead['firstName'] = "Joe"
  leads.append(lead)
  
  lead = {}
  lead['email'] = "jill@example.com"
  lead['firstName'] = "Jill"
  leads.append(lead)
  
  json_leads = json.dumps(leads, separators=(',', ':'))
  
  print(json_leads)
  </code></pre>
  
  <p>Then the output is exactly the same within Microsoft Azure Databricks, but the Marketo system returns me an <code>609</code>-> Invalid JSON.</p>
  
  <p>My output looks like</p>
  
  <pre><code>[{"email":"joe@example.com","firstName":"Joe"},{"email":"jill@example.com","firstName":"Jill"}]
  </code></pre>
  
  <p>Its exactly the same like in the sample. When i use the sample JSON codeline it works, but my self generated JSOn does not work. </p>
  
  <p>Anyone has an idea what this ould be? I am using Python within Microsoft Azure Databricks.</p>