我正在嘗試讀取 .csv 文件并收到此錯誤ValueError: could not convert string to float: '???220'到目前為止，這是我的代碼：import csvimport matplotlibimport osenvironment = []# Initialise data dirdir = os.getcwd()print(dir)parent = os.path.dirname(dir)parent = os.path.dirname(parent)parent = os.path.dirname(parent)basedir = os.path.dirname(parent)print(basedir)datadir = os.path.join(basedir, 'data')print(datadir)inputdatadir = os.path.join(datadir, 'input')print(inputdatadir)# Open file and read.file = os.path.join(inputdatadir, 'snowslope1.csv')f = open(file, newline='') reader = csv.reader(f, quoting=csv.QUOTE_NONNUMERIC)for row in reader: # A list of rows    rowlist = []    for value in row: # A list of value        rowlist.append(value)        #print(value)    environment.append(rowlist)f.close()# Plot environment.matplotlib.pyplot.imshow(environment)matplotlib.pyplot.show()有人可以幫忙解決這里出了什么問題嗎？我不確定錯誤在哪里，因為它們似乎都只是這樣的數字：我的文件 Snowslope1.csv 中的 220,221,222,223