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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 uni_to_beta(text):
 """ Convert unicode text to a betacode equivalent. This method can handle tónos or oxeîa characters in the input. Args: text: The text to convert to betacode. This text does not have to all be Greek polytonic text, and only Greek characters will be converted. Note that in this case, you cannot convert to beta and then back to unicode. Returns: The betacode equivalent of the inputted text where applicable. """

    u = _UNICODE_MAP

    transform = []

    for ch in text:
        try:
            conv = u[ch]
        except KeyError:
            conv = ch

        transform.append(conv)

    converted = ''.join(transform)
    return converted