title: How to split a dataframe string column into two columns?
body: <p>I have a data frame with one (string) column and I'd like to split it into two (string) columns, with one column header as '<code>fips'</code> and the other <code>'row'</code></p>
  <p>My dataframe <code>df</code> looks like this:</p>
  <pre><code>          row
  0    00000 UNITED STATES
  1    01000 ALABAMA
  2    01001 Autauga County, AL
  3    01003 Baldwin County, AL
  4    01005 Barbour County, AL
  </code></pre>
  <p>I do not know how to use <code>df.row.str[:]</code> to achieve my goal of splitting the row cell. I can use <code>df['fips'] = hello</code> to add a new column and populate it with <code>hello</code>. Any ideas?</p>
  <pre><code>         fips       row
  0    00000 UNITED STATES
  1    01000 ALABAMA 
  2    01001 Autauga County, AL
  3    01003 Baldwin County, AL
  4    01005 Barbour County, AL
  </code></pre>