<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def create_label_map(self, inplace=True):
 """ Creates mapping df based on ann_label_table and self.custom_labels. Table composed of entire WFDB standard annotation table, overwritten/appended with custom_labels if any. Sets __label_map__ attribute, or returns value. """


        label_map =  ann_label_table.copy()

        if self.custom_labels is not None:
            self.standardize_custom_labels()
            for i in self.custom_labels.index:
                label_map.loc[i] = self.custom_labels.loc[i]

        if inplace:
            self.__label_map__ = label_map
        else:
            return label_map