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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def positive_int(val):
 """Parse `val` into a positive integer."""

    if isinstance(val, float):
        raise ValueError('"{}" must not be a float'.format(val))
    val = int(val)
    if val >= 0:
        return val
    raise ValueError('"{}" must be positive'.format(val))