import firebirdsql

# connessione database
conn = firebirdsql.connect(
    host='localhost',
    database='/leadmanager/leadmanager.gdb',
    port=3050,
    user='****',
    password='****'
)

cursor = conn.cursor()

datins = "'10/10/18'"

cursor.execute("select id,nome,cognome,datins,idxesito,idxchiusura,usomarca,usomodello from lead where datins > " + datins)

for c in cursor.fetchall():
    print(c)

# chiusura connessione
conn.close()