#A function to input a date: John A. Oakey 2017
from datetime import date
#set variables for max and min year month and day
minyr, maxyr, minday, maxday, minmo, maxmo = 1900,2050,1,31,1,12
# this function will handle errors expected
def dateerror(inpart, datepart, thisdatein):
    if datepart == "tryerror":
        print(thisdatein + " is not a valid date. Please try again.")
        return()
    if datepart == 'xxxx':
        print (inpart + ' must be integers in this form: 00/00/0000. Please try again.')
        return()
    print(str(inpart) +" is not recognized as a "+ datepart + " that I can use. Please try again." )
    return()
#this function gets and vets the date - must be in the form mm/dd/yyyy
def getdate():
    #set up our global variables
    global yr
    global month
    global day
    #set up and implement while loop
    FetchAGoodDate = True
    while FetchAGoodDate:
        print("Please input a valid date between " + str(minyr) + " and "+ str(maxyr))
        date1=input("Please enter your date in the form mm/dd/yyyy: ")
# now look for problems with the input, check for minimum possible length
        if len(date1)<8:
            dateerror(date1,'input','date')
            continue
#...and tease out the values for month, day and year
        yr=date1[-4:]
        boundry=date1[-5]
        boundry2loc=date1.find(boundry,3,len(date1))
        month=date1[0:date1.find(boundry)]
        day=date1[date1.find(boundry)+1:boundry2loc]
#continue checking validity of all date components
        if (not yr.isdigit()) or (not month.isdigit()) or (not day.isdigit()):
            dateerror(date1,"xxxx",'date1')
            continue
        elif ((int(month)<minmo)  or (int(month) > maxmo)):
            dateerror(month,"month","code2")
            continue
        elif((int(day) < minday) or (int(day) > maxday)):
            dateerror(day,"day","code3")
            continue
        try:
            testdate = date(int(yr), int(month), int(day))
        except ValueError:
            dateerror(yr, "tryerror", date1)
            continue
#all error possibilities tested, so accept our date data and end loop
        FetchAGoodDate = False
    return(date1)
#proof that everything works
datein = getdate()
print("----------------------------------")
print("the date in: ", str(datein))
print("month", str(month))
print('day ',day)
print ("year input is: " +yr)
dateobj = date(int(yr),int(month),int(day))
print ("date object: ",dateobj)
print("date object for month: ",dateobj.month)