def copy_folder_content(src, dst):
    """
    Copy all content in src directory to dst directory.
    The src and dst must exist.
    """
    for file in os.listdir(src):
        file_path = os.path.join(src, file)
        dst_file_path = os.path.join(dst, file)
        if os.path.isdir(file_path):
            shutil.copytree(file_path, dst_file_path)
        else:
            shutil.copyfile(file_path, dst_file_path)