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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def get_field_for_object(field_type, field_id, form):
    '''
    This tag allows one to get a specific series or event form field
    in registration views.
    '''
    field_name = field_type + '_' + str(field_id)
    return form.__getitem__(field_name)