<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _dqdv_combinded_frame(cell, **kwargs):
 """Returns full cycle dqdv data for all cycles as one pd.DataFrame. Args: cell: CellpyData-object Returns: pandas.DataFrame with the following columns: cycle: cycle number voltage: voltage dq: the incremental capacity """


    cycles = cell.get_cap(
        method="forth-and-forth",
        categorical_column=True,
        label_cycle_number=True,
    )
    ica_df = dqdv_cycles(cycles, **kwargs)
    assert isinstance(ica_df, pd.DataFrame)
    return ica_df