import re


def is_core_dependency(filenm):
    """Check whether than named file is a core python dependency.

    If it is, then it's required for any frozen program to run (even the 
    bootstrapper).  Currently this includes only the python DLL and the
    MSVCRT private assembly.
    """
    if re.match("^(lib)?python\\d[\\d\\.]*\\.[a-z\d\\.]*$",filenm):
        return True
    if filenm.startswith("Microsoft.") and filenm.endswith(".CRT"):
        return True
    return False