You can use the assign function:

df = df.assign(industry='yyy')

If you only need to get list of unique values, you can just use unique method. If you want to have Python's set, then do set(some_series)

In [1]: s = pd.Series([1, 2, 3, 1, 1, 4])

In [2]: s.unique()
Out[2]: array([1, 2, 3, 4])

In [3]: set(s)
Out[3]: {1, 2, 3, 4}

However, if you have DataFrame, just select series out of it ( some_data_frame['<col_name>'] ).

If the column ranges are non-contiguous you will have to call set_column() for each range:

writer.sheets['Sheet1'].set_column('A:A', 15, my_format)
writer.sheets['Sheet1'].set_column('C:C', 15, my_format)

Note, to do this programmatically you can also use a numeric range:

for col in (0, 2):
    writer.sheets['Sheet1'].set_column(col, col, 15, my_format)

Rename Specific Columns

Use the df.rename() function and refer the columns to be renamed. Not all the columns have to be renamed:

Copydf = df.rename(columns={'oldName1': 'newName1', 'oldName2': 'newName2'})

# Or rename the existing DataFrame (rather than creating a copy) 
df.rename(columns={'oldName1': 'newName1', 'oldName2': 'newName2'}, inplace=True)

Minimal Code Example

Copydf = pd.DataFrame('x', index=range(3), columns=list('abcde'))
df

   a  b  c  d  e
0  x  x  x  x  x
1  x  x  x  x  x
2  x  x  x  x  x

The following methods all work and produce the same output:

Copydf2 = df.rename({'a': 'X', 'b': 'Y'}, axis=1)
df2 = df.rename({'a': 'X', 'b': 'Y'}, axis='columns')
df2 = df.rename(columns={'a': 'X', 'b': 'Y'}) 

df2

   X  Y  c  d  e
0  x  x  x  x  x
1  x  x  x  x  x
2  x  x  x  x  x

Remember to assign the result back, as the modification is not-inplace. Alternatively, specify inplace=True:

Copydf.rename({'a': 'X', 'b': 'Y'}, axis=1, inplace=True)
df

   X  Y  c  d  e
0  x  x  x  x  x
1  x  x  x  x  x
2  x  x  x  x  x
 

You can specify errors='raise' to raise errors if an invalid column-to-rename is specified.

Reassign Column Headers

Use df.set_axis() with axis=1.

Copydf2 = df.set_axis(['V', 'W', 'X', 'Y', 'Z'], axis=1)
df2

   V  W  X  Y  Z
0  x  x  x  x  x
1  x  x  x  x  x
2  x  x  x  x  x

Headers can be assigned directly:

Copydf.columns = ['V', 'W', 'X', 'Y', 'Z']
df

   V  W  X  Y  Z
0  x  x  x  x  x
1  x  x  x  x  x
2  x  x  x  x  x