Unable to achieve custom dateformat for df.to_excel using xlsxwriter

I am not able to achieve the dateformat using xlsxwriter. I have tried the sample code of date formatting to excel in pandas using xlsxwriter, but with slight variation by adding Sqldf step to filter out the df. here I have used only the simple filter in sqldf step for test puropose ,but have complex in real scenario.

can anybody suggest me , whats going worng here . I have checked the dtypes , it is object in both the working(actual example) and non-working(sqldf step added) case.

import pandas as pd
from datetime import datetime, date
from pandasql import sqldf

# Create a Pandas dataframe from some datetime data.
df = pd.DataFrame({'Date and time': [datetime(2015, 1, 1, 11, 30, 55),
                                     datetime(2015, 1, 2, 1,  20, 33),
                                     datetime(2015, 1, 3, 11, 10    ),
                                     datetime(2015, 1, 4, 16, 45, 35),
                                     datetime(2015, 1, 5, 12, 10, 15)],
                   'Dates only':    [date(2015, 2, 1),
                                     date(2015, 2, 2),
                                     date(2015, 2, 3),
                                     date(2015, 2, 4),
                                     date(2015, 2, 5)],
                   })

# Create a Pandas Excel writer using XlsxWriter as the engine.
# Also set the default datetime and date formats.
s_df =  sqldf('select * from df',locals())
writer = pd.ExcelWriter("pandas_datetime.xlsx",
                        engine='xlsxwriter',
                        datetime_format='mmm d yyyy hh:mm:ss',
                        date_format='mmmm dd yyyy')

# Convert the dataframe to an XlsxWriter Excel object.
s_df.to_excel(writer, sheet_name='Sheet1')

# Get the xlsxwriter workbook and worksheet objects in order to set the column
# widths, to make the dates clearer.
workbook  = writer.book
worksheet = writer.sheets['Sheet1']

worksheet.set_column('B:C', 20)

# Close the Pandas Excel writer and output the Excel file.
writer.save()

output :