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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 unique_digits(x):
    """Given a list of positive integers x. return a sorted list of all elements that hasn't any even digit. [1, 15, 33] [] """
    odd_digit_elements = []
    for i in x:
        if all (int(c) % 2 == 1 for c in str(i)):
            odd_digit_elements.append(i)
    return sorted(odd_digit_elements)
