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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 generate_if_then_else(self):
 """ Implementation of if-then-else. .. code-block:: python { 'if': { 'exclusiveMaximum': 0, }, 'then': { 'minimum': -10, }, 'else': { 'multipleOf': 2, }, } Valid values are any between -10 and 0 or any multiplication of two. """

        with self.l('try:'):
            self.generate_func_code_block(
                self._definition['if'],
                self._variable,
                self._variable_name,
                clear_variables=True
            )
        with self.l('except JsonSchemaException:'):
            if 'else' in self._definition:
                self.generate_func_code_block(
                    self._definition['else'],
                    self._variable,
                    self._variable_name,
                    clear_variables=True
                )
            else:
                self.l('pass')
        if 'then' in self._definition:
            with self.l('else:'):
                self.generate_func_code_block(
                    self._definition['then'],
                    self._variable,
                    self._variable_name,
                    clear_variables=True
                )