title: tally employee occurance in data frame within pandas, when column contains mulitple values
body: <p>i have the following excel file</p>
  
  <pre><code>ID     EmpName                   date           cost
  1      bob smith              01/01/2019     10
  2      Jane Doe               01/04/2019     20
  3      steve ray, bob smith   01/03/2017     100
  </code></pre>
  
  <p>If i want to count the occurrences of each person: bob, jane, and steve ... but on ID 3 (as well as other rows) the data in the name field has multiple employees listed which isn't ideal.. what is my best approach to tally this?  </p>
  
  <p>Looking for something like this</p>
  
  <pre><code>employee      count       cost
  bob smith     2           110
  jane doe      1           20
  steve ray     1           100
  </code></pre>
  
  <p><strong>Second question:</strong></p>
  
  <p>If my data is as follows: </p>
  
  <pre><code>ID     EmpName1      Empname2    date           cost
  1      bob smith                 01/01/2019     10
  2      Jane Doe                  01/04/2019     20
  3      steve ray     bob smith   01/03/2017     100
  </code></pre>
  
  <p>could this be tallied in a similar way? </p>