Query to Access a specfic data in the row using python
If I understand it correctly, you are storing all data in one field of the table? If so, MySQL will not be of much use as you need to unserialize the data in python. If so, then this question is not really for DBA, but more for StackOverflow.

If you however want to restructure the table and keep various data elements in different columns instead of one column called "data", then you could SELECT only that particular column(s) that are relevant instead of querying whole string.