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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_database_rows(self, tables=None, database=None):
 """Retrieve a dictionary of table keys and list of rows values for every table."""

        # Get table data and columns from source database
        source = database if database else self.database
        tables = tables if tables else self.tables

        # Get database select queries
        commands = self._get_select_commands(source, tables)

        # Execute select commands
        return self._execute_select_commands(source, commands)