Why Does Pandas Throw a ''DataFrame' Object Has No Attribute 'append'' Error?

Error: 'DataFrame' Object Has No Attribute 'Append'

Problem Description:

When attempting to append a dictionary to a DataFrame object, the error "'DataFrame' object has no attribute 'append'" is encountered. Despite the expectation that DataFrame has an "append" method, the error persists.

Code Sample:

df = pd.DataFrame(df).append(new_row, ignore_index=True)

Reason Behind the Error:

As of pandas version 2.0, the append method has been removed. It has been replaced by the concat method for the majority of use cases.

Alternative Approach Using Concat:

df = pd.concat([df, pd.DataFrame([new_row])], ignore_index=True)

Alternative Approach Using Loc (for RangeIndex Only):

If the index of the DataFrame is a RangeIndex, the loc method can be used.

df.loc[len(df)] = new_row

Why Append Was Removed:

The removal of append was prompted by the frequent misuse of the method by new pandas users. Unlike the append method in Python lists, pandas append does not modify the existing DataFrame; instead, it creates a new DataFrame, resulting in inefficient operations when performed repeatedly.

Best Practice for Repeated Insertion:

If multiple insertions are required, they should be collected in a list and converted to a DataFrame at the end, which can then be concatenated with the original DataFrame:

lst = []

for new_row in items_generation_logic:
    lst.append(new_row)

# create extension
df_extended = pd.DataFrame(lst, columns=['A', 'B', 'C'])

# concatenate to original
out = pd.concat([df, df_extended])

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