Pivot a column in list of dictionaries

I guess it depends on the complexity of the data structure
you might find pandas pivot useful

or for your example something simpler like

my_table = [{'period': 'Period 2020-08-01 to 2020-07-31', 'status': 'Open', 'username': 'Jane', 'amount': 180.32}, 
            {'period': 'Period 2020-08-01 to 2020-07-31', 'status': 'Open', 'username': 'John', 'amount': 154.0}]
my_new_dict = {'amount'+row['username'] : row['amount'] for row in my_table}