import pandas as pd
import os

from sqlalchemy import create_engine

user = os.environ["LOGNAME"]

def engcreate():
    global rdsEngine

    with open("/home/" + user + "/Credentials/Redshift_user", "r") as rds_user:
        rds_user = rds_user.read()

    with open("/home/" + user + "/Credentials/Redshift_pw", "r") as rds_pass:
        rds_pass = rds_pass.read()

    rds_url   = "prd-XX-redshift-rds.XXX1XXXXXXXX.us-east-1.redshift.amazonaws.com"
    rds_port  = "5439"
    rds_dbase = "databasename"
    rdsEngine = create_engine("postgresql://" + rds_user + ":" + rds_pass + "@" + rds_url + ":" + rds_port + "/" + rds_dbase)
    return

engcreate()

rdsQuery = """
SELECT *
FROM thetable
"""

df = pd.read_sql_query(rdsQuery, rdsEngine)