title: Can't convert object datatype to datetime format
body: <p>I want to convert a column into DateTime format and separate the date and time. I have already got the solution for datetime conversion as given 
  <a href="https://stackoverflow.com/questions/56554428/typeerror-an-integer-is-required-in-pandas-column">from the link below:</a> and code:</p>
  
  <pre><code>df2['date']=pd.to_datetime(df2['date'].astype(str), format='%Y%m%d%H%M',errors='coerce')
  </code></pre>
  
  <p>But, whenever I try to see the data type of df2['date'], the column is still an object datatype.
  When I try to separate it using the code:</p>
  
  <pre><code>df2['date'], df2['Time'] = df2['date'].dt.normalize(), df['date'].dt.time
  </code></pre>
  
  <p>it gives me error :</p>
  
  <pre><code>AttributeError: 'DataFrame' object has no attribute 'dt'
  </code></pre>
  
  <p>When I print df2.columns the output is</p>
  
  <pre><code>MultiIndex(levels=[[u'ALT', u'AW', u'CLG', u'DEWP', u'DIR', u'GUS', u'H', u'L', u'M', u'MAX', u'MIN', u'MW', u'PCP01', u'PCP06', u'PCP24', u'PCPXX', u'SD', u'SKC', u'SLP', u'SPD', u'STP', u'TEMP', u'VSB', u'W', u'date'], [u'F', u'GMT', u'MPH', u'Mb', u'Miles', u'Unnamed: 10_level_1', u'Unnamed: 12_level_1', u'Unnamed: 13_level_1', u'Unnamed: 14_level_1', u'Unnamed: 15_level_1', u'Unnamed: 16_level_1', u'Unnamed: 17_level_1', u'Unnamed: 18_level_1', u'Unnamed: 19_level_1', u'Unnamed: 20_level_1', u'Unnamed: 3_level_1', u'Unnamed: 6_level_1', u'Unnamed: 7_level_1', u'Unnamed: 8_level_1', u'Unnamed: 9_level_1', u'inches']],
             labels=[[24, 4, 19, 5, 2, 17, 7, 8, 6, 22, 11, 11, 11, 11, 1, 1, 1, 1, 23, 21, 3, 18, 0, 20, 9, 10, 12, 13, 14, 15, 16], [1, 15, 2, 2, 16, 17, 18, 19, 5, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 0, 0, 3, 20, 3, 0, 0, 20, 20, 20, 20, 20]])
  </code></pre>
  
  <p>and the output of df2.dtypes are:</p>
  
  <pre><code>date   GMT                     object
  DIR    Unnamed: 3_level_1      object
  SPD    MPH                    float64
  GUS    MPH                      int64
  CLG    Unnamed: 6_level_1      object
  SKC    Unnamed: 7_level_1      object
  L      Unnamed: 8_level_1      object
  M      Unnamed: 9_level_1      object
  H      Unnamed: 10_level_1     object
  VSB    Miles                  float64
  MW     Unnamed: 12_level_1     object
         Unnamed: 13_level_1     object
         Unnamed: 14_level_1     object
         Unnamed: 15_level_1     object
  AW     Unnamed: 16_level_1     object
         Unnamed: 17_level_1     object
         Unnamed: 18_level_1     object
         Unnamed: 19_level_1     object
  W      Unnamed: 20_level_1     object
  TEMP   F                        int64
  DEWP   F                       object
  SLP    Mb                      object
  ALT    inches                  object
  STP    Mb                      object
  MAX    F                       object
  MIN    F                       object
  PCP01  inches                  object
  PCP06  inches                  object
  PCP24  inches                  object
  
  PCPXX  inches                  object
  SD     inches                  object
  </code></pre>