def calc_batches(train_max: int, train_every: int, n: int) -> dict:
    batches = dict()
    # loop over up to as many records as you have
    for batch in range(n):
        # work out the start of the batch, with a max() to handle first batch
        start = max(train_every * batch, 1)
        # work out the end of the batch, with a min() to handle last batch
        end = min(train_max+(train_every * batch), n)
        # add batch info to the dictionary
        batches[batch+1] = {"start": start, "end": end}
        # break out once you have assigned all rows to a batch
        if end == n:
            break
    return batches
    
    
calc_batches(train_max=1000, train_every=500, n=10000)
  
'''
{1: {'start': 1, 'end': 1000},
 2: {'start': 500, 'end': 1500},
 3: {'start': 1000, 'end': 2000},
 4: {'start': 1500, 'end': 2500},
 5: {'start': 2000, 'end': 3000},
 6: {'start': 2500, 'end': 3500},
 7: {'start': 3000, 'end': 4000},
 8: {'start': 3500, 'end': 4500},
 9: {'start': 4000, 'end': 5000},
 10: {'start': 4500, 'end': 5500},
 11: {'start': 5000, 'end': 6000},
 12: {'start': 5500, 'end': 6500},
 13: {'start': 6000, 'end': 7000},
 14: {'start': 6500, 'end': 7500},
 15: {'start': 7000, 'end': 8000},
 16: {'start': 7500, 'end': 8500},
 17: {'start': 8000, 'end': 9000},
 18: {'start': 8500, 'end': 9500},
 19: {'start': 9000, 'end': 10000}}  
'''