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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 gen_yaml_category():
    '''
    find YAML.
    '''
    for wroot, _, wfiles in os.walk('./database/meta'):
        for wfile in wfiles:
            if wfile.endswith('.yaml'):
                gen_category(os.path.join(wroot, wfile), wfile[0])