Write an iterator that acts as the built-in range iterator in Python. You should account for all different cases:

  1. When there is only one input, the argument acts as the ending value with 0 as the start value.
  2. When there is only two inputs, the arguments act as the start and end, respectively.
  3. When there are three inputs, they act as the start, end, and step values.

Also, remember that range starts from start and goes up to, but not including end.

class Range(object):
    >>> r = Range(3) # 0, 1, 2
    >>> s = Range(1, 5) # 1, 2, 3, 4
    >>> t = Range(1, 5, 2) # 1, 3
    "***YOUR CODE HERE***"

Toggle Solution

class Range(object):

    def __init__(self, start, end=None, step=1):
        if end is None:
            end = start
            start = 0

        self.start = start
        self.end = end
        self.step = step

    def __iter__(self):
        return self

    def __next__(self):
        if self.start >= self.end:
            raise StopIteration
        current = self.start
        self.start += self.step
        return current

The tricky part about this question is the __init__ method. As long as you pay particular attention to the different ways of creating a Range object, you should be good to go.

I don't claim to be perfect so if you find an error on this page, please send me an email preferably with a link to this page so that I know what I need to fix!

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