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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 evaluate_unicode(self, value):
 """Evaluate Unicode."""


        if value.startswith('u8'):
            length = 1
            value = value[3:-1]
            encoding = 'utf-8'
        elif value.startswith('u'):
            length = 2
            value = value[2:-1]
            encoding = 'utf-16'
        else:
            length = 4
            value = value[2:-1]
            encoding = 'utf-32'

        def replace_unicode(m):
            """Replace Unicode."""

            groups = m.groupdict()
            esc = m.group(0)
            value = esc
            if groups.get('special'):
                # Handle basic string escapes.
                value = BACK_SLASH_TRANSLATION[esc]
            elif groups.get('char') or groups.get('oct'):
                # Handle character escapes.
                integer = int(esc[2:], 16) if groups.get('char') else int(esc[1:], 8)
                if (
                    (length < 2 and integer <= 0xFF) or
                    (length < 4 and integer <= 0xFFFF) or
                    (length >= 4 and integer <= 0x10FFFF)
                ):
                    try:
                        value = chr(integer)
                    except Exception:
                        value = ' '
            return value

        return self.norm_nl(RE_UESC.sub(replace_unicode, value).replace('\x00', '\n')), encoding