title: Iterate through Calendar Month Beginning/End
body: <p>I would like to create a loop that returns for each month during the provide time period, the first day and last day (taking into account that months end on the 28th-31st day): ("function_to_increase_month" is not defined yet)</p>
  
  <pre><code>for beg in pd.date_range('2014-01-01', '2014-06-30', freq='1M'):
  period_start = beg
  period_end = function_to_increase_month(beg)
  </code></pre>
  
  <p>The expected output being for the first iteration:
      period_start = '2014-01-01'
      period_end = '2014-01-31'</p>
  
  <p>Second Iteration:
      period_start = '2014-02-01'
      period_end = '2014-02-28'</p>
  
  <p>Third Iteration:
      period_start = '2014-03-01'
      period_end = '2014-03-31'</p>
  
  <p>Can anyone suggest an approach?</p>