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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 parse_info(wininfo_name, egginfo_name):
 """Extract metadata from filenames. Extracts the 4 metadataitems needed (name, version, pyversion, arch) from the installer filename and the name of the egg-info directory embedded in the zipfile (if any). The egginfo filename has the format:: name-ver(-pyver)(-arch).egg-info The installer filename has the format:: name-ver.arch(-pyver).exe Some things to note: 1. The installer filename is not definitive. An installer can be renamed and work perfectly well as an installer. So more reliable data should be used whenever possible. 2. The egg-info data should be preferred for the name and version, because these come straight from the distutils metadata, and are mandatory. 3. The pyver from the egg-info data should be ignored, as it is constructed from the version of Python used to build the installer, which is irrelevant - the installer filename is correct here (even to the point that when it's not there, any version is implied). 4. The architecture must be taken from the installer filename, as it is not included in the egg-info data. 5. Architecture-neutral installers still have an architecture because the installer format itself (being executable) is architecture-specific. We should therefore ignore the architecture if the content is pure-python. """


    egginfo = None
    if egginfo_name:
        egginfo = egg_info_re.search(egginfo_name)
        if not egginfo:
            raise ValueError("Egg info filename %s is not valid" % (egginfo_name,))

    # Parse the wininst filename
    # 1. Distribution name (up to the first '-')
    w_name, sep, rest = wininfo_name.partition('-')
    if not sep:
        raise ValueError("Installer filename %s is not valid" % (wininfo_name,))

    # Strip '.exe'
    rest = rest[:-4]
    # 2. Python version (from the last '-', must start with 'py')
    rest2, sep, w_pyver = rest.rpartition('-')
    if sep and w_pyver.startswith('py'):
        rest = rest2
        w_pyver = w_pyver.replace('.', '')
    else:
        # Not version specific - use py2.py3. While it is possible that
        # pure-Python code is not compatible with both Python 2 and 3, there
        # is no way of knowing from the wininst format, so we assume the best
        # here (the user can always manually rename the wheel to be more
        # restrictive if needed).
        w_pyver = 'py2.py3'
    # 3. Version and architecture
    w_ver, sep, w_arch = rest.rpartition('.')
    if not sep:
        raise ValueError("Installer filename %s is not valid" % (wininfo_name,))

    if egginfo:
        w_name = egginfo.group('name')
        w_ver = egginfo.group('ver')

    return {'name': w_name, 'ver': w_ver, 'arch': w_arch, 'pyver': w_pyver}