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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 _build_js(inputs, outputs, name, implementation, support_code):
 """Creates a BigQuery SQL UDF javascript object. Args: inputs: a list of (name, type) tuples representing the schema of input. outputs: a list of (name, type) tuples representing the schema of the output. name: the name of the function implementation: a javascript function defining the UDF logic. support_code: additional javascript code that the function can use. """

    # Construct a comma-separated list of input field names
    # For example, field1,field2,...
    input_fields = json.dumps([f[0] for f in inputs])

    # Construct a json representation of the output schema
    # For example, [{'name':'field1','type':'string'},...]
    output_fields = [{'name': f[0], 'type': f[1]} for f in outputs]
    output_fields = json.dumps(output_fields, sort_keys=True)

    # Build the JS from the individual bits with proper escaping of the implementation
    if support_code is None:
      support_code = ''
    return ('{code}\n{name}={implementation};\nbigquery.defineFunction(\'{name}\', {inputs}, '
            '{outputs}, {name});').format(code=support_code, name=name,
                                          implementation=implementation, inputs=str(input_fields),
                                          outputs=str(output_fields))