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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 add_file_to_tree(tree, file_path, file_contents, is_executable=False):
 """Add a file to a tree. Args: tree A list of dicts containing info about each blob in a tree. file_path The path of the new file in the tree. file_contents The (UTF-8 encoded) contents of the new file. is_executable If ``True``, the new file will get executable permissions (0755). Otherwise, it will get 0644 permissions. Returns: The provided tree, but with the new file added. """

    record = {
        "path": file_path,
        "mode": "100755" if is_executable else "100644",
        "type": "blob",
        "content": file_contents,
        }
    tree.append(record)
    return tree