Am looking to download the following fields (list below) for SP500 index constituents, from 1995 to yesterday, daily data. Am using the following 
import refinitiv.data as 
from refinitiv.data.content import fundamental_and_reference
import datetime
rd.open_session()
growth_fields = ["TR.EPSMeanEstLastToNextYrGrowth",
                 "TR.EPSLTGEstValue(Period=FY1)",
                 "TR.LTGMean",
                 "TR.RevenueSmartEstFwdYrGrowth",
                 "TR.OrganicSalesGrowthMean(Period=FY1)",
                 "TR.GrowthCapexActValue(Period=FY0)",
                 "ROE",
                 "TR.ReturnonAvgCommEqtyPctIncomeAvailabletoCommExclExtraItems5YrAvg(Period=FY0)",
                 "TR.ROICActValue(Period=FY0)",
                 "TR.NetProfitMargin(Period=FY0)",
                 "TR.OperatingMarginPercent(Period=FY0)",
                 "TR.GrossMargin(Period=FY0)",
                 "TR.EBITDAMarginPercent(Period=FY0)",
                 "TR.LTDebtToTtlCapitalPct(Period=FY0)",
                 "TR.TtlDebtToTtlEquityPct(Period=FY0)",
                 "TR.EBITIntCov(Period=FY0)"]
lse = fundamental_and_reference.Definition(
    ["0#.INX"],
    fields = growth_fields
).get_data()
Ho do i specify a start and end date? it appears that there are lot of missing data in the cross section, so I am looking to download a time series, and I would like to have a login in place to have the latest available data if the most recent for a given date is not yet available. Ho do I do this?