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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 guess_folder_vcs(folder):
 """ Given a path for a folder on the local filesystem, see what kind of vcs repo it is, if any. """

    try:
        contents = os.listdir(folder)
        vcs_folders = ['.git', '.hg', '.svn']
        found = next((x for x in vcs_folders if x in contents), None)
        # Chop off the dot if we got a string back
        return found[1:] if found else None
    except OSError:
        return None