def interpolate_range(a,b,s=5):
    """ Generate consecutive values list between two numbers with optional step (default=5)."""
    if (a == b):
        return [a]
    else:
        mx = max(a,b)
        mn = min(a,b)
        result = []
        # inclusive upper limit. If not needed, delete '+1' in the line below
        while(mn < mx + 1):
            # if step is positive we go from min to max
            if s > 0:
                result.append(mn)
                mn += s
            # if step is negative we go from max to min
            if s < 0:
                result.append(mx)
                mx += s
        return result