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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 to_str(self):
        '''Convert to string.'''
        pairs = []
        for name, value in self.get_all():
            if value and self._wrap_width:
                pairs.append('{0}:{1}'.format(
                    name,
                    '\r\n'.join(textwrap.wrap(
                        value, width=self._wrap_width,
                        drop_whitespace=False, initial_indent=' ',
                        subsequent_indent=' '
                    ))
                ))
            elif value:
                pairs.append('{0}: {1}'.format(name, value))
            else:
                pairs.append('{0}:'.format(name))

        pairs.append('')
        return '\r\n'.join(pairs)