title: object to datetime conversion_ converting from mm/dd/yyyy object value type to date type (python, pandas)
body: <p>All variables are object dtype. I'd like to convert the dtype from object to datetime. </p>
  
  <pre><code>    df = pd.DataFrame(
                      {"ID":['A','B','C','D','E'],
                       "date":['4/12/2017','4/27/2017','4/28/2017','4/29/2017','4/210/2017'],
                       })
  </code></pre>
  
  <p>What I've 3 different approaches. First,  </p>
  
  <pre><code>df['date'] = pd.to_datetime(df['date'], format="%m-%d-%Y")
  </code></pre>
  
  <p>This didn't work out, giving me value error saying "time data '4/12/2017' doesn't match format specified"  </p>
  
  <p>Second,  </p>
  
  <pre><code>parse(exerciseCsv['mostRecentExerciseDate'], dayfirst=True)
  </code></pre>
  
  <p>Third,</p>
  
  <pre><code>[datetime.strptime(x, '%m/%d/%Y') for x in exerciseCsv['mostRecentExerciseDate']]
  </code></pre>
  
  <p>All of above didn't work out. This looks like a simple task, can anyone help me how to get this done and explain me why this isn't working? </p>