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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 check_recommended_files(data, vcs):
 """Do check for recommended files. Returns True when all is fine. """

    main_files = os.listdir(data['workingdir'])
    if not 'setup.py' in main_files and not 'setup.cfg' in main_files:
        # Not a python package.  We have no recommendations.
        return True
    if not 'MANIFEST.in' in main_files and not 'MANIFEST' in main_files:
        q = ("This package is missing a MANIFEST.in file. This file is "
             "recommended. "
             "See http://docs.python.org/distutils/sourcedist.html"
             " for more info. Sample contents:"
             "\n"
             "recursive-include main_directory *"
             "recursive-include docs *"
             "include *"
             "global-exclude *.pyc"
             "\n"
             "You may want to quit and fix this.")

        if not vcs.is_setuptools_helper_package_installed():
            q += "Installing %s may help too.\n" % \
                vcs.setuptools_helper_package
        # We could ask, but simply printing it is nicer.  Well, okay,
        # let's avoid some broken eggs on PyPI, per
        # https://github.com/zestsoftware/zest.releaser/issues/10
        q += "Do you want to continue with the release?"
        if not ask(q, default=False):
            return False
        print(q)
    return True