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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 missing_requirements_command(missing_programs, installation_string, filename, unused_lines):
 """Pseudo-command to be used when requirements are missing."""

    verb = 'is'
    if len(missing_programs) > 1:
        verb = 'are'
    return {
        filename: {
            'skipped': [
                '%s %s not installed. %s' % (', '.join(missing_programs), verb,
                                             installation_string)
            ]
        }
    }