def verify_attr_existence(self, table_name, attr_name):
self.verify_table_existence(table_name)<EOL>if self.has_attr(table_name, attr_name):<EOL><INDENT>return<EOL><DEDENT>raise AttributeNotFoundError(<EOL>"<STR_LIT>".format(attr_name, table_name)<EOL>)<EOL>
:param str table_name: Table name that the attribute exists.
:param str attr_name: Attribute name to tested.
:raises simplesqlite.AttributeNotFoundError:
    If attribute not found in the table
:raises simplesqlite.TableNotFoundError:
    |raises_verify_table_existence|

:Sample Code:
    .. code:: python

        from simplesqlite import (
            SimpleSQLite,
            TableNotFoundError,
            AttributeNotFoundError
        )

        table_name = "sample_table"
        con = SimpleSQLite("sample.sqlite", "w")
        con.create_table_from_data_matrix(
            table_name,
            ["attr_a", "attr_b"],
            [[1, "a"], [2, "b"]])

        con.verify_attr_existence(table_name, "attr_a")
        try:
            con.verify_attr_existence(table_name, "not_existing")
        except AttributeNotFoundError as e:
            print(e)
        try:
            con.verify_attr_existence("not_existing", "attr_a")
        except TableNotFoundError as e:
            print(e)
:Output:
    .. parsed-literal::

        'not_existing' attribute not found in 'sample_table' table
        'not_existing' table not found in /tmp/sample.sqlite