Refactored __init__.py to improve imports and maintainability

Author: TMVKasiViswanath

prometheus_api_client/__init__.py

@@ -1,9 +1,9 @@
-
 """A collection of tools to collect and manipulate prometheus metrics."""
 
 __title__ = "prometheus-connect"
 __version__ = "0.5.7"
 
+from .exceptions import PrometheusApiClientException, MetricValueConversionError
 def __getattr__(name):
     if name == "PrometheusConnect":
         from .prometheus_connect import PrometheusConnect
@@ -20,4 +20,4 @@ def __getattr__(name):
     elif name == "MetricRangeDataFrame":
         from .metric_range_df import MetricRangeDataFrame
         return MetricRangeDataFrame
-    raise AttributeError(f"module {__name__} has no attribute {name}")
+    raise AttributeError(f"module {__name__} has no attribute {name}")