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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 validate(source):
 """Validate a Wagon archive. Return True if succeeds, False otherwise. It also prints a list of all validation errors. This will test that some of the metadata is solid, that the required wheels are present within the archives and that the package is installable. Note that if the metadata file is corrupted, validation of the required wheels will be corrupted as well, since validation checks that the required wheels exist vs. the list of wheels supplied in the `wheels` key. """

    _assert_virtualenv_is_installed()

    logger.info('Validating %s', source)
    processed_source = get_source(source)
    metadata = _get_metadata(processed_source)

    wheels_path = os.path.join(processed_source, DEFAULT_WHEELS_PATH)
    validation_errors = []

    logger.debug('Verifying that all required files exist...')
    for wheel in metadata['wheels']:
        if not os.path.isfile(os.path.join(wheels_path, wheel)):
            validation_errors.append(
                '{0} is missing from the archive'.format(wheel))

    logger.debug('Testing package installation...')
    tmpenv = _make_virtualenv()
    try:
        install(source=processed_source, venv=tmpenv)
        if not _check_installed(metadata['package_name'], tmpenv):
            validation_errors.append(
                '{0} failed to install (Reason unknown)'.format(
                    metadata['package_name']))
    finally:
        shutil.rmtree(tmpenv)

    if validation_errors:
        logger.info('Validation failed!')
        for error in validation_errors:
            logger.info(error)
        logger.info('Source can be found at: %s', processed_source)
    else:
        logger.info('Validation Passed!')
        if processed_source != source:
            shutil.rmtree(processed_source)
    return validation_errors