def gross_lev(positions):
exposure = positions.drop('<STR_LIT>', axis=<NUM_LIT:1>).abs().sum(axis=<NUM_LIT:1>)<EOL>return exposure / positions.sum(axis=<NUM_LIT:1>)<EOL>
Calculates the gross leverage of a strategy.

Parameters
----------
positions : pd.DataFrame
    Daily net position values.
     - See full explanation in tears.create_full_tear_sheet.

Returns
-------
pd.Series
    Gross leverage.