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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 long2str(l):
 """Convert an integer to a string."""

    if type(l) not in (types.IntType, types.LongType):
        raise ValueError('the input must be an integer')

    if l < 0:
        raise ValueError('the input must be greater than 0')
    s = ''
    while l:
        s = s + chr(l & 255)
        l >>= 8

    return s