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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 _formatparam(param, value=None, quote=True):
 """Convenience function to format and return a key=value pair. This will quote the value if needed or if quote is true. If value is a three tuple (charset, language, value), it will be encoded according to RFC2231 rules. If it contains non-ascii characters it will likewise be encoded according to RFC2231 rules, using the utf-8 charset and a null language. """

    if value is not None and len(value) > 0:
        # A tuple is used for RFC 2231 encoded parameter values where items
        # are (charset, language, value).  charset is a string, not a Charset
        # instance.  RFC 2231 encoded values are never quoted, per RFC.
        if isinstance(value, tuple):
            # Encode as per RFC 2231
            param += '*'
            value = utils.encode_rfc2231(value[2], value[0], value[1])
            return '%s=%s' % (param, value)
        else:
            try:
                value.encode('ascii')
            except UnicodeEncodeError:
                param += '*'
                value = utils.encode_rfc2231(value, 'utf-8', '')
                return '%s=%s' % (param, value)
        # BAW: Please check this.  I think that if quote is set it should
        # force quoting even if not necessary.
        if quote or tspecials.search(value):
            return '%s="%s"' % (param, utils.quote(value))
        else:
            return '%s=%s' % (param, value)
    else:
        return param