diff --git a/components/espcoredump/corefile/elf.py b/components/espcoredump/corefile/elf.py
index 4ce1eabf8d..82527cf72e 100644
--- a/components/espcoredump/corefile/elf.py
+++ b/components/espcoredump/corefile/elf.py
@@ -164,7 +164,6 @@ class ElfFile(object):
         sha256.update(elf_bytes)
         self.sha256 = sha256.digest()
 
-
     @staticmethod
     def _parse_string_table(byte_str, offset):  # type: (bytes, int) -> str
         section_name_str = byte_str[offset:]
diff --git a/components/espcoredump/corefile/loader.py b/components/espcoredump/corefile/loader.py
index 880c974eff..dbf292d517 100644
--- a/components/espcoredump/corefile/loader.py
+++ b/components/espcoredump/corefile/loader.py
@@ -88,7 +88,7 @@ class EspCoreDumpVersion(object):
 
     COREDUMP_SUPPORTED_TARGETS = XTENSA_CHIPS + RISCV_CHIPS
 
-    def __init__(self, version=None):  # type: (int) -> None
+    def __init__(self, version=None):  # type: (Optional[int]) -> None
         """Constructor for core dump version
         """
         super(EspCoreDumpVersion, self).__init__()
@@ -248,7 +248,7 @@ class EspCoreDumpLoader(EspCoreDumpVersion):
         else:
             raise NotImplementedError
 
-    def _extract_elf_corefile(self, exe_name=None, e_machine=ESPCoreDumpElfFile.EM_XTENSA):  # type: (str, int) -> None
+    def _extract_elf_corefile(self, exe_name=None, e_machine=ESPCoreDumpElfFile.EM_XTENSA):  # type: (Optional[str], int) -> None
         """
         Reads the ELF formatted core dump image and parse it
         """