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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 _pip_search(stdout, stderr):
 """Callback for pip search."""

        result = {}
        lines = to_text_string(stdout).split('\n')
        while '' in lines:
            lines.remove('')

        for line in lines:
            if ' - ' in line:
                parts = line.split(' - ')
                name = parts[0].strip()
                description = parts[1].strip()
                result[name] = description

        return result