Change the position of column in python code example

Example 1: python more order of columns

In [7]: cols = df.columns.tolist()
In [8]: cols
Out[8]: [0L, 1L, 2L, 3L, 4L, 'mean']

In [12]: cols = cols[-1:] + cols[:-1]

In [13]: cols
Out[13]: ['mean', 0L, 1L, 2L, 3L, 4L]
  
In [14]: df = df[cols]

Example 2: pandas reorder columns

# Get column list in ['item1','item2','item3'] format 
df.columns
# [0]output: 
Index(['item1','item2','item3'], dtype='object')

# Copy just the list protion of the output and rearrange the columns 
cols = ['item3','item1','item2']

# Resave dataframe using new column order
df = df[cols]