Python compare data from sqlite database is between two date

#import module
import sqlite3

#database path is here
database = 'test.db'

#Testing in the data
#25.09.2017 27.09.2017
#01.10.2017 03.10.2017

class db_conn:
    ''' Class connect main '''
    def __init__(self, db, Fdata=None, Sdata=None):
        self.db = db
        self.Fdata = Fdata
        self.Sdata = Sdata
        self.con = sqlite3.connect(self.db)

    def insert(self):
        ''' insert into database two value's '''
        self.con.execute("INSERT INTO praznik (Fdata, Sdata) VALUES (?, ?)", (self.Fdata, self.Sdata))
        self.con.commit()
        self.con.close()


    def show_table(self):
        ''' Use for select from database '''
        self.cur = self.con.cursor()
        self.cur.execute("SELECT * from praznik")
        for row in self.cur:
            print("First Data {fdata} - Second Data {sdata}".format(fdata=row[1], sdata=row[2]))
        self.con.close()


    def check_period(self, fdata_check, ldata_check):
        ''' check period is valid or not '''
        self.fdata_check = fdata_check
        self.ldata_check = ldata_check
        self.cur = self.con.cursor()
        self.cur.execute("SELECT * from praznik")
        for row in self.cur:
            if row[1] <= self.ldata_check and row[2] >= self.fdata_check:
                print("Problem")
                break
            else:
                print("Look Good")
                break
        self.con.close()