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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 apt_cache(in_memory=True, progress=None):
 """Build and return an apt cache."""

    from apt import apt_pkg
    apt_pkg.init()
    if in_memory:
        apt_pkg.config.set("Dir::Cache::pkgcache", "")
        apt_pkg.config.set("Dir::Cache::srcpkgcache", "")
    return apt_pkg.Cache(progress)