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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 pretty_format(obj, indent=None):
 """ Pretty formats the given object as a string which is returned. If indent is None, a single line will be returned. """

        if indent is None:
            if isinstance(obj, TLObject):
                obj = obj.to_dict()

            if isinstance(obj, dict):
                return '{}({})'.format(obj.get('_', 'dict'), ', '.join(
                    '{}={}'.format(k, TLObject.pretty_format(v))
                    for k, v in obj.items() if k != '_'
                ))
            elif isinstance(obj, str) or isinstance(obj, bytes):
                return repr(obj)
            elif hasattr(obj, '__iter__'):
                return '[{}]'.format(
                    ', '.join(TLObject.pretty_format(x) for x in obj)
                )
            else:
                return repr(obj)
        else:
            result = []
            if isinstance(obj, TLObject):
                obj = obj.to_dict()

            if isinstance(obj, dict):
                result.append(obj.get('_', 'dict'))
                result.append('(')
                if obj:
                    result.append('\n')
                    indent += 1
                    for k, v in obj.items():
                        if k == '_':
                            continue
                        result.append('\t' * indent)
                        result.append(k)
                        result.append('=')
                        result.append(TLObject.pretty_format(v, indent))
                        result.append(',\n')
                    result.pop()  # last ',\n'
                    indent -= 1
                    result.append('\n')
                    result.append('\t' * indent)
                result.append(')')

            elif isinstance(obj, str) or isinstance(obj, bytes):
                result.append(repr(obj))

            elif hasattr(obj, '__iter__'):
                result.append('[\n')
                indent += 1
                for x in obj:
                    result.append('\t' * indent)
                    result.append(TLObject.pretty_format(x, indent))
                    result.append(',\n')
                indent -= 1
                result.append('\t' * indent)
                result.append(']')

            else:
                result.append(repr(obj))

            return ''.join(result)