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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 render_json(tree, indent):
 """Converts the tree into a flat json representation. The json repr will be a list of hashes, each hash having 2 fields: - package - dependencies: list of dependencies :param dict tree: dependency tree :param int indent: no. of spaces to indent json :returns: json representation of the tree :rtype: str """

    return json.dumps([{'package': k.as_dict(),
                        'dependencies': [v.as_dict() for v in vs]}
                       for k, vs in tree.items()],
                      indent=indent)