title: Convert the UTC datetime to local datetime in pandas
body: <p>I have a data frame that consists the UTC_Time and the Timezone_info. I need to convert the UTC_Time to local_time. I have the following code but it is not working. Is there a way to do this efficiently (I can use a for loop and it works but I want to avoid for loop if possible).</p>
  
  <pre><code>        UTC_Time         Timezone_info
  0  2018-02-12 18:16:00       America/New_York
  1  2018-02-15 11:39:00    America/Puerto_Rico
  2  2018-02-15 22:17:00    America/Los_Angeles
  3  2018-02-17 00:59:00      America/Guayaquil
  4  2018-02-17 11:34:00  America/Santo_Domingo
  </code></pre>
  
  <p>The code I am trying to use is:
  <code>data['local_time']=data['UTC_Time'].dt.tz_localize('UTC').dt.tz_convert(data['Timezone_info'])</code></p>
  
  <p>But this does not work.</p>
  
  <p>The for loop that makes it work (but is probably the slowest way to do it is):</p>
  
  <pre><code>data['local_time']=0
  for i in range(len(data)):
      tz=data.at[i,'Timezone_info']
      data.at[i,'local_time']=data.at[i,'UTC_Time'].tz_localize(data).tz_convert(tz)
  </code></pre>
  
  <p>What would be the pythonic way to do it?</p>