Added a hex-bin.py file in conversion.py

conversions/hex-bin.py

@@ -0,0 +1,67 @@
+#convert hexadecimal into binary
+from doctest import testmod
+import math
+
+def convert(num: str) -> str:
+
+    """
+    Convert a hexadecimal value to its decimal equivalent
+    #https://stackoverflow.com/questions/1425493/convert-hex-to-binary
+    >>> convert("AC")
+    10101100
+    >>> convert("9A4")
+    100110100100
+    >>> convert("   12f   ")
+    100101111
+    >>> convert("FfFf")
+    1111111111111111
+    >>> convert("F-f")
+    Traceback (most recent call last):
+    ...
+    ValueError: invalid literal for int() with base 16:
+    >>> convert()
+    Traceback (most recent call last):
+    ...
+    ValueError: Empty string was passed to the function:
+
+    """
+
+    bin_str : str=""
+    flag :bool = 0
+    hex_str :str = num.strip()
+
+    if not hex_str:
+        raise ValueError("Empty string was passed to the function")
+    is_negative : bool= hex_str[0] == "-"
+
+    if is_negative:
+        flag = 1
+        hex_string = hex_str[1:]
+
+    num2 :int = int(hex_str, 16)
+
+    """
+    Here, we have used " >> " bitwise operator
+    Bitwise right shift: 
+    Shifts the bits of the number to the right and fills 0 on voids left as a result. 
+    Similar effect as of dividing the number with some power of two.
+    Example: 
+    a = 10
+    a >> 1 = 5 
+
+    """
+
+    while num2>0:
+        num3 :str = str(num2%2)
+        bin_str = num3 + bin_str
+        num2=num2>>1
+
+    if flag: 
+        return "-"+bin_str
+    else:
+        return bin_str
+
+
+if __name__ == "__main__":
+    testmod(name = 'convert', verbose = True)
+