import mysql.connector
import numpy as np

cnx = mysql.connector.connect(user='user', password='pw, host='ip_here')
for i,j in enumerate(columnList):
   cursor.execute('SELECT `' + j + '` FROM `table_name`
   iValues = cursor.fetchall()
   cursor.close
   if i == 0:
      extractedValues = iValues
   else:
      extractedValues = np.hstack((extractedValues, iValues))

cnx.close