Added left calendar dates parsing

hashes.py

@@ -0,0 +1,34 @@
+import hashlib
+
+def calculate_sha1(filepath):
+    """
+    Calculates the SHA1 hash of a given file.
+
+    Args:
+        filepath (str): The path to the file.
+
+    Returns:
+        str: The hexadecimal representation of the SHA1 hash, or None if the file is not found.
+    """
+    sha1_hash = hashlib.sha1()
+    try:
+        with open(filepath, "rb") as f:
+            # Read the file in chunks to handle large files efficiently
+            for chunk in iter(lambda: f.read(4096), b""):
+                sha1_hash.update(chunk)
+        return sha1_hash.hexdigest()
+    except FileNotFoundError:
+        print(f"Error: File not found at {filepath}")
+        return None
+    except Exception as e:
+        print(f"An error occurred: {e}")
+        return None
+
+
+if __name__ == "__main__":
+    # Example usage:
+    file_path = "xls.xls"  # Replace with the actual path to your file
+    sha1_result = calculate_sha1(file_path)
+
+    if sha1_result:
+        print(f"The SHA1 hash of '{file_path}' is: {sha1_result}")