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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 relpath_to_modname(relpath):
 """Convert relative path to module name Within a project, a path to the source file is uniquely identified with a module name. Relative paths of the form 'foo/bar' are *not* converted to module names 'foo.bar', because (1) they identify directories, not regular files, and (2) already 'foo/bar/__init__.py' would claim that conversion. Args: relpath (str):
 Relative path from some location on sys.path Example: 'ballet.util._util' """

    # don't try to resolve!
    p = pathlib.Path(relpath)

    if p.name == '__init__.py':
        p = p.parent
    elif p.suffix == '.py':
        p = p.with_suffix('')
    else:
        msg = 'Cannot convert a non-python file to a modname'
        msg_detail = 'The relpath given is: {}'.format(relpath)
        logger.error(msg + '\n' + msg_detail)
        raise ValueError(msg)

    return '.'.join(p.parts)