Add stock data source parameter

Add `force_data_source` parameter to Stock.__init__ allowing
manual selection of data source ('twse' or 'tpex'), this also
implied that we will not check if the stock ID exist in the database
or not.

For example, the TPEX has some warrants:

上櫃認購(售)權證,70000U,譜瑞群益39售07
上櫃認購(售)權證,70001U,宣德國票3A售01

which does not exist in the latest codes.

Perhaps someone would like to know their history price,
if they update the codes, twstock will block them down.

But, in this commit, you can explicit passing which data source
you want, and implicitly bypass the stock ID check:

 # Skip stock ID validation (use with caution)
 stock = twstock.Stock('731120', force_data_source="twse")

Author: mlouielu

twstock/stock.py

@@ -160,9 +160,29 @@ def purify(self, original_data):
         return [self._make_datatuple(d) for d in original_data["tables"][0]["data"]]
 
 
+DATA_FETCHER = {
+    "twse": TWSEFetcher,
+    "tpex": TPEXFetcher,
+}
+
+
 class Stock(analytics.Analytics):
-    def __init__(self, sid: str, initial_fetch: bool = True):
-        if sid not in codes:
+    def __init__(
+        self,
+        sid: str,
+        initial_fetch: bool = True,
+        force_data_source: str = None,
+    ):
+        """
+        Args:
+            sid (str): Stock ID
+            initial_fetch (bool): Fetch data when initializing
+            force_data_source (str): Force data source, can be 'twse' or 'tpex',
+                if not set, will use the data source from stock codes database,
+                if set, it also implied that we will not check if the stock ID is in the database.
+        """
+
+        if force_data_source is None and sid not in codes:
             raise StockIDNotFoundError(
                 f'Stock ID "{sid}" not found in database.\n'
                 "Either you misspelled it or it is not in the database.\n"
@@ -172,9 +192,9 @@ def __init__(self, sid: str, initial_fetch: bool = True):
             )
 
         self.sid = sid
-        self.fetcher = (
-            TWSEFetcher() if codes[sid].data_source == "twse" else TPEXFetcher()
-        )
+        self.fetcher = DATA_FETCHER.get(
+            force_data_source if force_data_source else codes[sid].data_source
+        )()
         self.raw_data = []
         self.data = []