Using .values.max() for arrays

I use the following code to get a row from a dataframe and then find the max value.

def find_max(a):
    return a.values.max()

row = df.iloc[0].astype(int)
max_value = find_max(a)

That works fine. However, if I pass an array like

ar = [1,2,3]
max_value = find_max(ar)

it doesn’t work and I receive AttributeError: 'list' object has no attribute 'values'. How can I use that function for both types?

>Solution :

def find_max(a):
    if isinstance(a, list):
        return max(a)
    elif isinstance(a, pd.DataFrame):
        return a.values.max()
    else:
        print("No max method found for the input type")